Date   

2010's Status in the Receiver World

Jordan Dobrikin <jjdobrikin@...>
 


Hi 
some bedside reading.  
It would be interesting to see an SW Radio Shootout
thanx 
73 de jordan ve7jjd 

Radio Jay Allen AM Radio Shootout 
Features & Ergonomics: Older radios were analog with simple tuning dials and controls. Most (but not all) current radios are digital, and the tuned frequency is locked in perfectly and displayed digitally. Most digital radios have many features, such as direct frequency entry via a keypad, clocks, timers, many memory presets, auto scanning and more. Either type of radio can perform well or poorly…it depends on how well it is designed. There are good reasons to prefer either…I tend to use both types for different jobs. I enjoy band scanning on my old analog radios but I also use digitals to hop from one frequency to another quickly. There is no best choice. 
Please remember that these radios are rated within groups only…they are not in descending order within the groups except as noted. I will occasionally comment when a radio is near the top or bottom of its group – also note that most of these radios have full reviews on this site…a few will be upcoming. I also welcome your comments and questions at radiojayallen@...…those with general interest will be posted in the Q and A column under the Reader’s Questions Tab. 
The Contestants (In Groups Rated For Overall AM Reception– Models Within Groups Approximately Equal Except As Noted) – Capsule Reviews follow the lists.  
***** Five Stars; The Crème de la Crème  7 Radios    Five star radios provide AM reception as good as it gets in a portable radio…these days you usually get excellent FM reception as well. They will pull in weak and medium strength signals with an absolute minimum of background noise and let you hear any signal that is receivable in a given location. But remember – if noise limits your reception, an excellent radio may do little or no better than a poor radio. For more information on improving your AM reception see my article Combating AM and SW Interference.  Within  groups radios are approximately equal overall except as noted, but may have different strengths and weaknesses described in the capsule reports that follow the listings…most of these have full reviews as well…there will be links to them in the capsule reports. 
 **** 1/2 – Four and 1/2 Star      10  Radios   Still excellent, Four and 1/2 Star radios are very close to the top radios except for very slightly more background hiss on weak to medium strength signals and sometimes a bit less selectivity. But you won’t hear the difference between these and the best radios unless your local noise floor is low. In many if not most settings these radios will therefore perform just as well as the very best radios. They may also have other features or qualities that make them very desirable in many circumstances. I consider the Four 1/2 Star and Four Star radios to be truly excellent AM portables.  
-----------------------------------------------------------
****Four Stars 7 Radios   Including Sony ICF 2010
*** 1/2 Three & 1/2 Stars   6 Radios    *** 1/2 Star Radios are still very good performers which I just could not squeak into the 4 Star Group:
*** Three Stars;   12 Radios  *** Three Star Radios are very good AM radios, but show another step down in performance. These radios may have other strengths making them very worthwhile, but these ratings are for sensitivity and overall performance as stand-alone AM portables. Still, if you have noise problems these may perform just as well as the more sensitive radios above…these are still very nice sets. 
**1/2 Two & 1/2 Stars 4 Radios   **1/2 Star Radios are actually quite close to the three star radios above but occasionally fall just a hair short of them. They will match the three star radios in many ways on many stations but may fall just a hair short in others…sometimes it’s just a difference in the number of stations they sound authoritative on and it requires very complete tests to notice the differences. In other words, they are highly recommended. 
** Two Stars          z  Radios    ** Star Radios are still decently performing AM radios. While they will give you more hiss in the background on medium to weak daytime signals they are still good enough to provide enjoyable reception of typical signals.  At night when most AM signals are stronger and sensitivity may be a bit less important they can be fine for scanning the bands to see what’s out there…the ** radios are no slouches and are generally at least as good as the average table radio.
*1/2  One & 1/2 Stars   6 Radios   ** Star Radios are still decently performing AM radios. While they will give you more hiss in the background on medium to weak daytime signals they are still good enough to provide enjoyable reception of typical signals.  At night when most AM signals are stronger and sensitivity may be a bit less important they can be fine for scanning the bands to see what’s out there…the ** radios are no slouches and are generally at least as good as the average table radio.
* One Star  19 Radios     * Star Radios are usually smaller travel-sized or Walkman-style radios, perfect for stowing in luggage, but also fun for just playing around with at home. They can’t be expected to compete with the radios above – not only do they contain smaller ferrite rod antennas but they are usually less expensive designs. Nevertheless, the best of these radios are remarkably good for their size, some feature DSP (Digital Signal Processing) and excel in FM performance. In fact, a subset of the radio hobby has sprung up called the Ultra-Lighters…their Ultra-Light Radios must be no more than 20 cubic centimeters and cost no more than $100 in order to qualify, yet these dedicated hobbyists log stations from all over the world with some of these radios “barefoot” (using no external antennas or aids), while others experiment with modifications or use huge antennas to feed signals into these tiny sets. Often the skill of the operator, which includes traveling to better reception areas or improving conditions at one’s home, is more important than the quality of the radio in achieving good results and the Ultra-Lighters exemplify that concept. They are serious hobbyists and have achieved some amazing results using these small radios. But be aware that the Ultralighters, who often chase Trans-Atlantic or Trans-Pacific DX, often value selectivity above sensitivity because those foreign signals are sandwiched between domestic signals, and also, if you are using an external antenna, sensitivity may be less important than selectivity and overload resistance. 
****Four Stars: 
Eton E1**** (Because it uses a whip antenna rather than a ferrite rod for AM it performs less well when there is local noise which can render it nearly useless…in low nose areas its AM is very good. See capsule and full reports for more. 
GE P-780/783/784 Series**** GE’s 1958 tour de force design demonstrated how good transistor portables could  be – a great radio! 
ITT-101/102/103**** Most powerful sounding audio anywhere near this size and super AM selectivity. Good FM. 
Panasonic RF-4900/DR-49**** A tank of a radio doesn’t match the RF-2200’s AM but beats it on SW. Good FM.  
-----------------------------------------------------------------------------------------------
Sony ICF-2010**** An all-time classic still beats all current production portables on SW – FM average.   
****Four Stars – Just a small notch lower in sensitivity but still far better than most 
Sony ICF-2010**** Sony ICF-2010 – A landmark radio for Sony during the early days of digital. I love the 2010 and have owned several. I still use mine quite often, but although it is a classic in every sense of the word, with strong performance in many areas, including better synchronous detection than many of the current crop of mid-priced radios along with excellent SW reception with its whip antenna, its raw AM performance has been eclipsed by the radios above it on this list. On my band scans it was unable to hear any trace of some of the very weak signals which I could pick up on the more sensitive radios…a victim of a bit of unsuppressed digital noise. Some, not all, of the medium strength AM signals seemed a bit noisy on it too, partly due to its extremely crisp frequency response…this same character which helps the 2010 make weak SW signals decipherable also makes noise more obvious for the program listener. The 2010 is still a joy to use with the simplest memory system of any multi-band radio and legendary Sony quality. And for SW band-scanning using just its whip antenna, it is still a joy to use. FM performance is ordinary…fairly sensitive but not very selective by modern standards. Better SW than any currently made portable.
----------------------------------------------------------------------------------------------
Zenith Royal 755-LF-LG-LK **** Zenith’s popular lunchbox size AM series of portables are solid, easy to work on and run forever on 6 C cells. 
Zenith Royal 760 Navigator/780 Navigator/790/97M Super Navigator **** Slightly less sensitive AM than the 755 Zeniths above.   
==================================================================



Kona, Hawaii Ultralight DXpedition-- Asian TP-DX Results (Part 1)

Gary DeBock
 

From December 17-20 I had the chance to chase Asian DX from an ocean side beach alongside my motel in Kona on the west coast of the Big Island of Hawaii. The term "chase" is a little misleading, since I was pretty much swamped with huge Asian signals from 0730-1030 UTC every evening-- to the point where sunrise TP-DXing was foregone because my digital recorders were already becoming maxed out. My DXing gear was a new 7.5" (19cm) loopstick C.Crane Skywave SSB Ultralight radio and a TSA-friendly 5" (13cm) diameter "Frequent Flyer" FSL antenna. The modified portable was able to track down several "big gun" TP's all by itself at S9 levels, but the 5" FSL made all the difference in digging out the weaker stations.
The stampede of Asian signals every evening resulted in wild snarls with the Pacific Island DU's, as well as potent mixes of Japanese, Chinese and Korean stations. South Korean "Beehive" jammers added to the confusion on 801, 819 and 855, while two Chinese stations were fighting it out on 837. Trying to sort out and identify all the Chinese stations was impossible in the confusion, and even the idea of sending out some type of coherent daily TP-DXing summary was impossible because of the sheer number of wild Asian recordings. The only strategy that could work was to "record like mad" in Hawaii, and then upon return home write up a detailed summary after extensive file review.  Several frequencies were so snarled that even the recordings didn't help. The loggings and recordings listed below include several powerful stations which maxed out the Ultralight portable's bar-graph S-meter, which are identified with a double asterisk (**). For anyone feeling bored with his AM-DXing hobby, I strongly recommend a trip to Hawaii as the ultimate, permanent cure!
558  UnID   Japanese-sounding intonation for a few seconds at 0933 on 12-18, but a little too much Maui splatter to be sure   https://dreamcrafts.box.com/s/7mijy4ayyz2xpjjl9e893i46ud31l38z
603  HLSA   Namyang, S. Korea  (500 kW)   Modest-level Korean male conversation and American classic pop ("I'd Love You to Love Me," by Lobo) at 0922 on 12-20  https://dreamcrafts.box.com/s/0wc2ljb23siw9xalnrsdqk5mtt70p900   
612  JOLK   Fukuoka, Japan  (100 kW)   Japanese male and female speech at 0920 on 12-20; not a great performer for the power level  https://dreamcrafts.box.com/s/6hefy6p87kc8hrm69wai6lo2wncwc40x 
612  UnID   Female-voiced English speech and unusual music at 0904 on 12-18; Chuck and Mauno have suggested ABC (4QR) as a possible source, and although no other Australian stations showed up during the trip, that seems like the most likely possibility  https://dreamcrafts.box.com/s/wap9svgfchami7n4s1iop4z2z5cjjgki 
**621  China   (Heilongjiang?)   This prolific station was one of three powerhouses (along with North Korea and Tuvalu) which made the frequency a snarling mess on most evenings. It seemed to get a major boost whenever it was competing with Tuvalu, such as at 1002 on 12-18  https://dreamcrafts.box.com/s/w4ulfpkb1dbwou2rrjg3ncpnar56mrar
 When it was all alone it was somewhat more sedate, as at 1010 on 12-18
 **621  Pyongyang BS/ Voice of Korea   Chongjin, N. Korea  (500 kW)   The buzzing transmitter of N.K.'s Japanese service had serious power, snarling both Tuvalu and China at times. The usual North Korean music was played, with robotic Japanese announcers voicing adulation of Kim Jong Un and his ancestors. This typical music was at 0850 on 12-20  https://dreamcrafts.box.com/s/rhfksf381csgtohluxt3e97tjf79fshm
ID in Japanese by lady at 0951 on 12-20, followed by the usual ancient music
**657  Pyongyang BS   Kangnam, N. Korea  (1,500 kW)   The usual west coast N.K. big gun was often troubled by Honolulu splatter but pretty strong when it broke through, as at 0857 on 12-18  https://dreamcrafts.box.com/s/unaxxl72uzejpa59plxo2w3sonzdfoqx 
**666  JOBK   Osaka, Japan  (100 kW)   Predictably strong with Japanese male conversation // 675 at 0918 on 12-20; because 594 was covered with Honolulu splatter, this and 729 were the strongest NHK1 stations
 675  NHK1 Synchros   Hakodate/ Yamaguchi, Japan  (5 kW/ 5 kW)   Very good signal for these lower-powered relays at 0915 on 12-20  https://dreamcrafts.box.com/s/kz267eu3w8ev2a0vodqxuc9iw4927y94
 675  UnID-TP   Asian language co-channel mixing with NHK1 synchros at 1003 on 12-19; sounds like Chinese or Vietnamese   https://dreamcrafts.box.com/s/l7jxb9q34pgeslfn8ftn5rpbhikxofxr
 729  JOCK   Nagoya, Japan  (50 kW)   Very good signal with Japanese female speech at 0856 on 12-20; slight trace of a Chinese co-channel was heard underneath at times
 **747  JOIB   Sapporo, Japan  (500 kW)   This was the strongest Japanese station overall, usually with local-like signals and never any co-channels. These NHK2 English lessons at 0913 on 12-19 were at typical strength
 **774  JOUB   Akita, Japan  (500 kW)   Plenty strong, but not quite up to its 747 parallel's level. This Japanese stock market report at 0833 on 12-18 was at its usual strength 
 783  China   (Voice of Straight?)   Good signal with Chinese opera every night around 0900. This female-voiced opera was at 0916 on 12-19  https://dreamcrafts.box.com/s/2fajh29wb6givv89f0sl30iwzsqmuz9l
Male-voiced opera at good strength at 0914 on 12-18    https://dreamcrafts.box.com/s/6hg82m62pvgryla5fw7cyrwv0ezdaipq 
 801  UnID-TP   (Guam?)   During a fade in the Pyongyang BS/ Jammer signal this apparent Christian-format female vocal music was received at 0931 on 12-18, but there was nothing definite to determine identity
 801  Pyongyang BS   Kimchaek, N. Korea  (500 kW)   This was the weakest of the five North Korean stations received, and it was often pestered by the South Korean "Beehive" jammer on the frequency. It was strongest at 0842 on 12-20 with this ancient vocal music  https://dreamcrafts.box.com/s/e4kr0asg24d1ujyk74zztcbdl8aepazh
 801  Jammer    South Korean "Beehive" jammer mixing with Pyongyang BS' female vocal music at 0928 on 12-18. This was the usual strength of the N. Korean station (pretty anemic), and also the usual strength of the jammer
 **819  KCBS   Pyongyang, N. Korea  (500 kW)   Far and away the strongest North Korean station, and one of the top three Asian signals on the band each evening (along with 747-JOIB and 981-CNR1). Bizarre, ancient music and stern monologs were common, along with weird girl-group choral numbers at overpowering strength [like this one from the Moranbong Band ("Your Bosom is the Best")* at 1035 on 12-19]    https://dreamcrafts.box.com/s/gj2deffl7mjuzqr5tocsro100sfhqll9
"Let's Defend Socialism," originally by the Pochambo Electronic Ensemble** (another girl group) building in strength at 0823 on 12-20  https://dreamcrafts.box.com/s/h0gksa2xxmb8ql3ofqalo7j9o4yt1y3q
Ancient music, ID and 3+1 time pips at 0930 on 12-20 (both the country's TOH and the time pips are on the half hour) https://dreamcrafts.box.com/s/v7q9eniu9qq1f27rbq97v4c9zbni2eha
** Video at  https://www.youtube.com/watch?v=BIoOPH7kpCs   Thanks to Chris Kadlec for the information and links)
 819  Jammer   South Korean "Beehive" jammer mixing with KCBS in between songs at the 22 second point (just after the female vocal music) at 0853 on 12-18
 837  China Mix   Two Chinese stations were fighting it out on this frequency almost every evening, such as at 0937 on 12-20. No idea who they were, but they certainly had the frequency to themselves during this trip
 855  Pyongyang BS   Sangwon, N. Korea  (500 kW)   Medium-strength N.K. station playing the usual ancient music and stern monologs, complete with its own South Korean jammer at times. This female Korean speech was at 0832 on 12-20    https://dreamcrafts.box.com/s/34r4oayh63kxxigc6hisu3t5bfhz1yeb
 855  Jammer   South Korean "Beehive" jammer having the edge over Pyongyang BS' ancient music at 0948 on 12-18; this was the most prolific S.K. jammer in Kona, although not anything close to the old 1053 noisemaker
 864  UnID TP-Mix   Apparent mix of Japanese male and Korean female (KBS?) speech at 1017 on 12-19, but nothing definite to nail down either one   https://dreamcrafts.box.com/s/is6djygeafwu3ny04em5a97ce8sskb6t  
 873  JOGB   Kumamoto, Japan  (500 kW)   A rather modest performer for the power level, it had a weak Chinese co-channel at times, such as during this Japanese stock market report at 0904 on 12-18   https://dreamcrafts.box.com/s/bgkiq9nkxhs4exoeu0izd45n1cwg7nbl
 891  HLKB (KBS)   Busan, S. Korea  (250 kW)   The strongest South Korean station, but usually in a snarling mix with NHK1's JOHK, as at 1023 on 12-19. KBS usually had the edge, however  
 891  JOHK   Sendai, Japan  (20 kW)   Good performance for the power level, but broadcasting on an already occupied frequency (snarling with KBS in Busan)   https://dreamcrafts.box.com/s/9189zf266ul3qwkw59n7inbyzrms33ym
 **909  UnID-Chinese   Bizarre chanting by children in apparent Chinese at a very strong level at 0956 on 12-18; Chris Kadlec says this may be from CNR6 (1000 kW) in the Hakka dialect   https://dreamcrafts.box.com/s/0siovz0ojkty9ocy0gzl40bnfrp7qxpo
A somewhat extended version of the above recording is linked below, with various other TP's mixing in at times https://dreamcrafts.box.com/s/ze1djtse64rzemp4q0aeehqlw24n6xg4  
918  China   Shandong, China  (200 kW)   Half hour time pips (4+1?) and Chinese ID at 1:00 into the recording at 1029 on 12-19, but generally mixing with an UnID Japanese station  https://dreamcrafts.box.com/s/6vo2vgwdev2jzm6vnovu2ddkucaxwojm
918  UnID-Japan   Japanese intonation by female speaker at 1029 on 12-19, but nothing definite to determine which one of four Japanese stations is in the mix with Shandong  https://dreamcrafts.box.com/s/6vo2vgwdev2jzm6vnovu2ddkucaxwojm
(TO BE CONTINUED)       


Phillip Fimiani sent you a Dropbox file

Phillip Fimiani
 

 
 


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Best Regards
Phil
KD2HTN / WA2069SWL
Long: 34.210293 Lat:-78.057048
FM04xf 30dl
______________________________


Re: UK MW received in Gran Canaria

Michael <michael.setaazul@...>
 

BBC Radio 5 on 693 and 909 kHz is almost the last bastion
of medium-wave resistance. Many other BBC medium-wave
frequences are shutting down, gently so as not to
enrage the peasants unduly...

Radio 4 on 198 kHz is still broadcasting, but many
radios no longer include the longwave band. Years ago
I boosted my brother's radio so that he could hear
198kHz in Bordeaux.

Michael UK
...........................................................

On Sonntag, 14. 01 18 23:03, Marc Coevoet sintsixtus@... [ultralightdx] wrote:
Op 14-01-18 om 23:43 schreef petersouthport1956@... [ultralightdx]:
> 693 BBC 5live
> https://youtu.be/hbhUccXmyS8
> Peter Wilson
> Las Palmas Canary Islands
During Daytime, I could receive it in the summer in Mimizan, under Bordeaux.
Just turn the ferrite between a Spanish station and the BBC.
Marc


Re: UK MW received in Gran Canaria

Marc Coevoet
 

Op 14-01-18 om 23:43 schreef petersouthport1956@... [ultralightdx]:
693 BBC 5live
https://youtu.be/hbhUccXmyS8
Peter Wilson
Las Palmas Canary Islands

During Daytime, I could receive it in the summer in Mimizan, under Bordeaux.

Just turn the ferrite between a Spanish station and the BBC.


Marc


--
The "Penguin" has arrived - and he's not going away - ever.
What's on Shortwave guide: choose an hour, go!
http://shortwave dot tk


UK MW received in Gran Canaria

Peter 1956
 

693 BBC 5live
https://youtu.be/hbhUccXmyS8
Peter Wilson
Las Palmas Canary Islands


Top 10 "Flamethrower" TP Signals in Kona, Hawaii

Gary DeBock
 

West coast DXers fed up with cold weather and even colder DXing conditions do have one ultimate solution for both problems-- take a quick flight to Hawaii. In Hawaii during the winter the main challenge isn't tracking down TP-DX... it's sorting out the wild TP signal snarls that occur when sunset sweeps over Asia.

During a five day trip to Kona (Big Island) last month over 100 TP-DX recordings were made, including the 10 awesome TP signals linked below. Most of them are probably familiar to TP-DXers here, but one of them apparently hasn't been received on the west coast for quite a few years (621-North Korea). These signals were all received at the ocean beach level at the Royal Kona Resort on the Big Island of Hawaii from December 17-20 using a 7.5 inch (19cm) loopstick C.Crane Skywave SSB Ultralight and a 5 inch (13cm) diameter "Frequent Flyer" FSL antenna (specifically designed to easily pass through airports). The antenna provides inductive coupling gain roughly similar to that of a 4 foot (1.2 meter) air core box loop, and a photo of it (and the modified Ultralight portable) is posted at  https://dreamcrafts.box.com/s/rhpgxnnqrzkxt5xq5ofc8arqwq0m4cmd

1)  621  Pyongyang BS (VOK Japanese service)   Pyongyang, N. Korea (500 kW)   This bizarre transmitter has an obvious buzzing sound, but was strong enough to snarl badly with 621-Tuvalu on most nights. The Japanese service plays the usual North Korean music, with robotic Japanese announcers praising Kim Jong Un and his ancestors. This typical clip was recorded at 0850 on 12-20, temporarily sending Tuvalu down into the noise
https://dreamcrafts.box.com/s/rhfksf381csgtohluxt3e97tjf79fshm

2)  621  Radio Tuvalu   Funafuti, Tuvalu  (5 kW)   One of the exotic Pacific island stations that's very easy to receive in Hawaii, this station had a rough time with Pyongyang BS (above) and 621-China on most evenings after 0730 UTC. This strong signal features the usual female announcer providing local employment offers at 0750 on 12-18  https://dreamcrafts.box.com/s/chbg6d1b3xfskb7axw7vhvwae07o0y6c

3)  666  JOBK   Osaka, Japan  (100 kW)   No big surprise here, although the 594 NHK1 parallel was hammered by Hawaii splatter. Japanese male conversation was at a local-like level at 0918 on 12-20 https://dreamcrafts.box.com/s/5sm6pogm45wuukbggvhb8q9i8klpyqh5

4)  747  JOIB  Sapporo, Japan  (500 kW)   Overall the strongest Japanese station in Kona, with awesome signals and never any co-channels. The only Japanese station that ever came close in strength was 1134-JOQR, although that had some KBS competition at times. This blowtorch signal was at 0913 on 12-19 https://dreamcrafts.box.com/s/5v5byw2vzvw7azxhzrgsz6j591qwtxyv

5)  774  JOUB   Akita, Japan  (500 kW)   The NHK2 flagship station sounded potent at 0857 on 12-18, but never quite up to its 747 parallel's strength (which is the opposite of the usual west coast situation) https://dreamcrafts.box.com/s/p9aiqrhx4ji22gwc7nehalybl46cetj0

6)  819  KCBS   Pyongyang, N. Korea  (500 kW)   Overwhelming signals were the order of the day every evening from this bizarre flagship of the KCBS network. This girl group song from the modern Moranbong Band was loud enough to wake up the dead at 1035 (just past local midnight) on 12-19 (thanks to Chris Kadlec for info) https://dreamcrafts.box.com/s/gj2deffl7mjuzqr5tocsro100sfhqll9

7)  846  Kiribati   Christmas Island, Kiribati  (10 kW)   This Pacific island station had the strongest signal of any such transmitter-- as long as the equipment didn't go on the blink. Multiple signal dropouts were observed, and variable programming delays from the 1440 source were recorded. When it was on the air awesome signals were common, however, such as at 0735 on 12-18   https://dreamcrafts.box.com/s/zbo418obgvvnj4kvlchxgryze60e2q0p

8)  981  CNR1   Changchun, China  (200 kW)   This was another overwhelming Asian signal after 0800 on most evenings, and was far and away the strongest Chinese station. This thunderous CNR1 theme music was received at 0900 on 12-18  https://dreamcrafts.box.com/s/0390gk266y2v675chc196nejoe6rqxnw

9)  1098  V7AB   Majuro, Marshall Islands  (25 kW)   Another Pacific island blowtorch showing up every evening around local Kona sunset, this was one of the very few island stations impervious to the Asian signal onslaught. This typical island music was received at 0815 on 12-18   https://dreamcrafts.box.com/s/ogc8kz73he7cwtln5gw6ljammluub5p0

10)  1134  JOQR   Tokyo, Japan  (100 kW)   The only commercial Japanese station to make this list, its fast-paced programming usually drowned out the KBS co-channel, as at 0945 on 12-20. Stronger than most NHK big guns! https://dreamcrafts.box.com/s/7wbk5ocbzaa5phxz9bnpr6bal4hqlzg7

Honorable Mention:  For technical reasons these two stations missed out on the Top 10.

909-Chinese was UnID (one of many such Chinese stations), and because of some Christmas music may possibly have been the 10 kW Taiwan station. Strong children's chanting in apparent Mandarin was heard at 0956 on 12-18  https://dreamcrafts.box.com/s/0siovz0ojkty9ocy0gzl40bnfrp7qxpo

1593-CNR1 would have made the list except it could never quite shake off its pesky NHK2 co-channel   https://dreamcrafts.box.com/s/eybu72zjipo1zb5gz6qh461cfomjly5s  

73 and Good DX,
Gary DeBock (DXing in Kona, Hawaii from December 17-20, 2017)

 


Re: [loopantennas] Re: [SonyICF20102001Dusergroup] energizer l91 lithium batteries

Andy
 

Carbon/zinc is a weak acid-based battery.

Alkaline != acid.

Jordan, I have a bridge to sell you, real cheap.

Andy



Re: [loopantennas] Re: [SonyICF20102001Dusergroup] energizer l91 lithium batteries

Jordan Dobrikin <jjdobrikin@...>
 

hi
"carbon/zinc" is an alkaline battery   

The Wikipedia article should be edited to show "Zinc-Carbon", "Zinc-chloride", and "Alkaline" are equally prone to leakage.

Chemistry and capacity[edit]

Primary cells[edit]

Primary (non-rechargeable) zinc–carbon (dry cell) AA batteries have around 400–900 milliamp-hours capacity, with measured capacity highly dependent on test conditions, duty cycle, and cut-off voltage. Zinc–carbon batteries are usually marketed as "general purpose" batteries. Zinc-chloride batteries store around 1000 to 1500 mAh are often sold as "heavy duty" or "super heavy duty". Alkaline batteries from 1700 mAh to 3000 mAh cost more than zinc-chloride batteries, but hold additional charge.

Non-rechargeable lithium iron disulfide batteries are manufactured for devices that use a lot of power, such as digital cameras, where their high cost is offset by longer running time between battery changes and more constant voltage during discharge. Another advantage of lithium disulfide batteries compared to alkaline batteries is that they don't tend to leak. This is particularly important in expensive equipment, where a leaking alkaline battery can cause damage to the point of requiring replacement of the equipment. Lithium iron disulfide batteries are intended for use in equipment compatible with alkaline zinc batteries. Lithium-iron disulfide batteries can have an open-circuit voltage as high as 1.8 volts, but the in-circuit voltage reduces, making this chemistry compatible with equipment intended for zinc-based batteries. A fresh alkaline zinc battery can have an open-circuit voltage of 1.6 volts, but an iron-disulfide battery with an open-circuit voltage below 1.7 volts is entirely discharged.[6]



Hi




Thanx
73 de Jordan ve7jjd

On Thu, Jan 4, 2018 at 6:50 PM, Andy ai.egrps@... [loopantennas] <loopantennas@...> wrote:
 

Jordan wrote:

   "Batteries with alkaline ingredients are susceptible to "leakage" Batteries with other chemistries are not known for having leakage problems. "

Sorry, but that is simply not true..

Many of us have experience cleaning up the mess (or more likely, discarding the battery holder or the electronic item) when another kind of battery leaked.  I've opened up a carbon/zinc battery and saw how the zinc casing erodes from use.  It's only a matter of time until it pokes through.

Andy




Re: Jordan's posts

Gary DeBock
 

Hi Guys,

Regarding the multiple posts to every electronic group in sight, it's kind of a borderline situation. There have been some complaints about posts that are irrelevant to Ultralight radio, and those complaints are certainly valid. The moderators will continue to assess the situation, and issue a warning about the irrelevant posts if necessary.

Gary DeBock (in Puyallup, WA, USA)



-----Original Message-----
From: keith beesley keith1226@... [ultralightdx]
To: ultralightdx
Sent: Thu, Jan 4, 2018 4:02 pm
Subject: Re: [ultralightdx] Jordan's posts

 
Jordan's posts often have little or nothing to do with ultralighting per se, but I happen to be interested in many radio-related topics, and I enjoy them.

Keith Beesley
Seattle WA USA 


On Thursday, January 4, 2018 3:36 PM, "petersouthport1956@... [ultralightdx]" <ultralightdx@...> wrote:


 
Do any of the posts on this group from Jordan Dobrokin have anything to do with ultralight radio, or is he/she a spammer?

Peter Wilson
Las Palmas
Canary Islands



Re: [loopantennas] Re: [SonyICF20102001Dusergroup] energizer l91 lithium batteries

Andy
 

Jordan wrote:

   "Batteries with alkaline ingredients are susceptible to "leakage" Batteries with other chemistries are not known for having leakage problems. "

Sorry, but that is simply not true.

Many of us have experience cleaning up the mess (or more likely, discarding the battery holder or the electronic item) when another kind of battery leaked.  I've opened up a carbon/zinc battery and saw how the zinc casing erodes from use.  It's only a matter of time until it pokes through.

Andy



Re: Jordan's posts

osage_archer
 

Jordan copies and pastes the same things to several radio-related groups whether they deal with the group's specific subject or not.  Fortunately it's easy just to skip the posts if you've seen them before.


Re: Jordan's posts

keith beesley
 

Jordan's posts often have little or nothing to do with ultralighting per se, but I happen to be interested in many radio-related topics, and I enjoy them.

Keith Beesley
Seattle WA USA 


On Thursday, January 4, 2018 3:36 PM, "petersouthport1956@... [ultralightdx]" wrote:


 
Do any of the posts on this group from Jordan Dobrokin have anything to do with ultralight radio, or is he/she a spammer?

Peter Wilson
Las Palmas
Canary Islands



Jordan's posts

Peter 1956
 

Do any of the posts on this group from Jordan Dobrokin have anything to do with ultralight radio, or is he/she a spammer?

Peter Wilson
Las Palmas
Canary Islands


Re: [loopantennas] Battery types and the problem of leakage

Jordan Dobrikin <jjdobrikin@...>
 

hi 
thanx for the response 

Are you comparing apples to apples ie. the same chemistry 
Also when all is said and done why one anyone continue to use an alkaline based battery or for that matter any other Primary single-use battery?

thanx again
73 de jordan ve7jjd

Hi




Thanx
73 de Jordan ve7jjd

On Thu, Jan 4, 2018 at 2:30 PM, alienrelics@... [loopantennas] <loopantennas@...> wrote:
 

In decades of repairing electronics, I pulled a lot of leaking Duracell alkalines out of remote controls and boom boxes, but rarely ever an Energizer alkaline. Alkaline leaks leave a lot of white residue, and a thin insulating coating on the metal. Hard to clean off, I find physical abrasion best after removing all the loose powder. A fiberglass brush works well, but don't breath in the fibers!


Carbon-zinc will keep for a long time, unless you use them even slightly. Then it is a matter of months at most before they spill all over. But they will completely corrode metal parts away in a short time. I've seen a lot of battery springs and contacts reduced to red-rust puddles of muck.

I've had bad luck with the alkalines included with a lot of remote controls. Not long before they are dead, and often leaking before they are dead. I don't even bother to use them any more.

I've been buying Kirkland alkalines (Costco) and have had very good luck with them. 

Steven J Greenfield AE7HD

---In loopantennas@..., <jjdobrikin@...> wrote :

hi
Duracell and Energizer are Brand Names and are used on top of of the type/chemistry name.
Batteries with alkaline ingredients are susceptible to "leakage" Batteries with other chemistries are not known for having leakage problems.
The Sony ICF 2010/2010D thrive with low noise; low self discharge; rechargeable; precharged; 1.2 volt; NiMH Batteries.   
thanx 73 de jordan ve7jjd

https://en.wikipedia.org/wiki/AA_battery 
   
AA battery  From Wikipedia, the free encyclopedia
This article is about the type of electric cell. For the military weapon, see anti-aircraft warfare.    
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (August 2012) (Learn how and when to remove this template message)
AA cells
The AA battery—also called a double A or Mignon (French for "dainty") battery—is a standard size single cell cylindrical dry battery. The IEC 60086 system calls it size R6, and ANSIC18 calls it size 15.[1] Historically, it is known as SP7 (Standard Power 7) or HP7 (High Power 7) in official documentation the United Kingdom, though it is colloquially known as a "double A battery".
AA batteries are common in portable electronic devices. An AA battery is composed of a single electrochemical cell that may be either a primary battery (disposable) or a rechargeable battery. The exact terminal voltage and capacity of an AA size battery depend on cell chemistry; however, devices designed for AA will usually only take 1.5 V unless specified by the manufacturer.
Introduced in 1907,[2] the AA battery size was standardized by the American National Standards Institute (ANSI) in 1947, but it had been in use in flashlights and electrical novelties before formal standardization. ANSI and IEC Battery nomenclature gives several designations for cells in this size, depending on cell features and chemistry.
Contents
    1 Dimensions
    2 Chemistry and capacity
        2.1 Primary cells
        2.2 Rechargeable cells
        2.3 Comparison
    3 Use
    4 See also
    5 References
    6 External links
Dimensions:  An AA cell measures 49.2–50.5 mm (1.94–1.99 in) in length, including the button terminal—and 13.5–14.5 mm (0.53–0.57 in) in diameter. The positive terminal button should be a minimum 1 mm high and a maximum 5.5 mm in diameter, the flat negative terminal should be a minimum diameter of 7 mm.[1] 14500 Lithium Batteries are longer if they feature a protection circuit up to 53mm.
Alkaline AA cells have a weight of roughly 23 g (0.81 oz),[3] lithium AA cells have a mass around 15 g (0.53 oz),[4] and rechargeable Ni-MH cells around 31 g (1.1 oz).[5]
Chemistry and capacity
Primary cells
Primary (non-rechargeable) zinc–carbon (dry cell) AA batteries have around 400–900 milliamp-hours capacity, with measured capacity highly dependent on test conditions, duty cycle, and cut-off voltage. 
Zinc–carbon batteries are usually marketed as "general purpose" batteries. (Alkaline)
 Zinc-chloride batteries store around 1000 to 1500 mAh are often sold as "heavy duty" or "super heavy duty" (Alkaline)
Alkaline batteries from 1700 mAh to 3000 mAh cost more than zinc-chloride batteries, but hold additional charge.
Non-rechargeable lithium iron disulfide batteries are manufactured for devices that use a lot of power, such as digital cameras, where their high cost is offset by longer running time between battery changes and more constant voltage during discharge. Another advantage of lithium disulfide batteries compared to alkaline batteries is that they don't tend to leak. This is particularly important in expensive equipment, where a leaking alkaline battery can cause damage to the point of requiring replacement of the equipment. Lithium iron disulfide batteries are intended for use in equipment compatible with alkaline zinc batteries. Lithium-iron disulfide batteries can have an open-circuit voltage as high as 1.8 volts, but the in-circuit voltage reduces, making this chemistry compatible with equipment intended for zinc-based batteries. A fresh alkaline zinc battery can have an open-circuit voltage of 1.6 volts, but an iron-disulfide battery with an open-circuit voltage below 1.7 volts is entirely discharged.[6]
Rechargeable cells
Rechargeable batteries in the AA size are available in multiple chemistries: nickel–cadmium (NiCd) with a capacity of roughly 600–1000 mAh,[7] nickel–metal hydride (NiMH) in various capacities of 1300–3500 mAh[citation needed], 1.2 volts and lithium ion. Lithium ion chemistry has a nominal voltage of 3.6-3.7 volts, and are referred to as 14500 Li-ion batteries rather than AA.
Nickel-zinc cell (NiZn) AAs are also available, but not widely used.
Comparison
Type  Zinc–Carbon  Alkaline RAM Li-FeS2  Li-ion NiCd NiMH  NiZn
IEC name R6 LR6 LR6 FR6  ? KR6  HR6 ZR6
ANSI/NEDA name 15D 15A 15A  15LF 14500 1.2K2 1.2H2  ?
Capacity under 50 mA constant drain  400–1700 mAh     1800–2600 mAh  1800–2600 mAh 2700–3400 mAh 600-840 mAh     600–1000 mAh     600–2850 mAh     1500–1800 mAh
Nominal voltage  1.5 V     1.5 V     1.5 V     1.5 V     3.6-3.7 V  1.2 V     1.2 V     1.6-1.65 V
Max. energy at nominal voltage and 50 mA drain 2.55 Wh 3.90 Wh 3.90 Wh 5.10 Wh 2.88-2.96 Wh 1.20 Wh 3.42 Wh 2.97 Wh
Rechargeable     No Some Yes No[8] Yes  Yes  Yes  Yes
Use In 2011, AA cells accounted for approximately 60% of alkaline battery sales in the United States. In Japan, 58% of alkaline batteries sold were AA, known in that country as tansan (単三). In Switzerland, AA batteries totaled 55% in both primary and secondary (rechargeable) battery sales.[9][10][11]
See also     List of battery sizes     Battery nomenclature
References
Classic (LR6) datasheet from energizer.com
"About Eveready®". Eveready. Retrieved August 8, 2017.
"Energizer Alkaline AA Battery Specification" (PDF). Product Datasheet. Energizer. Retrieved October 21, 2015.
"Energizer Lithium AA Battery Specification" (PDF). Energizer. Retrieved October 21, 2015.
"Energizer NiMH AA Battery Specification" (PDF). Energizer. Retrieved October 21, 2015.
Lithium Iron Disulfide Handbook and Application Manual, Version LI4.04, Energizer Battery Manufacturing Inc.
Bergveld, H; Kruijt, W; Notten, P (February 1999). "Electronic-network modelling of rechargeable NiCd cells and its application to the design of battery management systems". Journal of Power Sources. 72 (2): 143–158. doi:10.1016/S0378-7753(98)00188-8.
Lithium Iron Disulfide, Handbook and Application Manual
Absatzzahlen 2008 INOBAT 2008 statistics.
Life Cycle Impacts of Alkaline Batteries with a Focus on End-of-Life – EPBA-EU
Monthly battery sales statistics – MoETI – March 2011
External links Wikimedia Commons has media related to AA batteries.
    Datasheet for Energizer alkaline AA battery (E91)
    Datasheet for Energizer lithium AA battery (L91)
    Datasheet for Duracell alkaline AA battery (MN1500)
 This page was last edited on 3 January 2018, at 05:46.     Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.

Hi




Thanx
73 de Jordan ve7jjd

On Wed, Jan 3, 2018 at 2:02 PM, David O'Banion via Groups.Io <spacemissing=yahoo.com@groups.io> wrote:
Real Duracells, wherever they are made, are big-time leakers.

Energizers leak, too, but nowhere near as often.



From: Shutterbug via Groups.Io yahoo.com@ groups.io>
To: SonyICF20102001Dusergroup@ groups.io
Sent: Wednesday, January 3, 2018 8:26 AM
Subject: Re: [SonyICF20102001Dusergroup] energizer l91 lithium batteries

Just my 2 cents......

I purchased many rechargeable alkaline batts (aaa, aa, c & d) over about 3 years and ALL, several brands, leaked. Before discarding the offenders, I checked the voltage and all were 1.4v or greater. They were used in communication gear, cameras, flashlights, items associated with computers, etc.

Since then, I use batts purchased from Sam's (Sam's brand) and NONE have leaked and all have worked well. 

Charlie



On ‎Wednesday‎, ‎January‎ ‎3‎, ‎2018‎ ‎09‎:‎52‎:‎58‎ ‎AM‎ ‎CST, JOE <k1ike@...> wrote:


There is a store here in Connecticut called Ocean State Job Lot.  The
last time I was in the store I saw a sign above the Energizer battery
display that said the battery packages with the photo of the Energizer
bunny were made in China.  Anyone else notice this?  I'm really cautious
of batteries made in China, but that's probably the way the
manufacturing of batteries is going in the future.

On that subject, watch out for a country of origin called PRC. This is
just another way of saying China, People's Republic of China. I've seen
this stamp on hardware and wonder if it is meant to dissuade you of
realizing it was actually made in China.

Joe


On 1/3/2018 8:19 AM, Russ Edmunds wrote:
> In my experience, the worst offenders for early leakage are Duracell
> Coppertop AA and AA cells. I switched over to Energizer alkalines
> about a year ago and so far no problems. The disclaimer here is that
> there have been multiple reports of 'fake' Duracells in the
> marketplace, so it's hard to be sure whether I had those or real ones,
> but when I contacted Duracell, their response was
> rather disappointing.









Re: [loopantennas] Beveridge Antennas

Jordan Dobrikin <jjdobrikin@...>
 

hi 
thanx for the timely response 
I have several antennas on my balcony and a store bought long wire on the 3 stories roof. 
On the balcony is a C.Crane Twin loop on a rotator and on the extended mast a HDTV/VHF yagi on a rotator.
This works well in keeping a/the Scanner focused on the Airport(s). 
I am planning the Beveridge's "because it can be done" and I have relativly little problem(s) in accessing the real estate. 
thanx again
73 de jordan ve7jjd


Hi




Thanx
73 de Jordan ve7jjd

On Thu, Jan 4, 2018 at 4:53 AM, W2XJ w2xj@... [loopantennas] <loopantennas@...> wrote:
 

My first impression is that there are massive legal issues. I can’t see this happening in a senior citizens home enviroment. Assuming I am wrong, alternatives a,b and c will have massive electrical issues due to the proximity of the wires to the fence support.. The PVC option might work depending on the band, length of the fence as well as the aforementioned potential legal issues. Technically you would need a minimum straight run of fence pointing in the desired direction. From a practical perspective, I think a loop inside a window is a better option. 

_____________________________
From: Jordan Dobrikin jjdobrikin@... [loopantennas] <loopantennas@...>
Sent: Thursday, January 4, 2018 2:06 AM
Subject: [loopantennas] Beveridge Antennas
To: Loop Antennas <loopantennas@...>, primetimeshortwave <primetimeshortwave@yahoogroups.com>, shortwave-radio <shortwave-radio@yahoogroups.com>, shortwave-swl-antenna <shortwave-swl-antenna@yahoogroups.com>, Shortwaveradios <shortwaveradios@yahoogroups.com>, ultralightdx <ultralightdx@...>, RICK WALD <rickawald@...>, <icf2010@...>



 


Hi 
I am looking for information comment advice and/or assistance in designing and building Receive Only long wire/Beveridge antennas at my new QTH. It is a combination 2 3 & 4 story wood frame construction Senior Citizens Apartment/Assisted complex surrounded by a chain-link fence and adjacent to a large open undeveloped Lot covered in grass weeds and light underbrush. 

I am considering several mechanical types of long wires Beveridges and "Baby Beverages".  
The most correct would be PVC pipe extensions of the fenceposts to support the wire 2 to 3 feet above the top rail of the fence. However, that would somewhat obtrusive and costly.  

I am considering stealth/semi-stealth antennas the simplest laying out wire on the ground on the adjacent Lot.  
 
An alternative is to use the chain link fence for mechanical support of insulated wire 
a) Using zip ties to attach the wire to the top pipe/rail 
b) Weaving the insulated wire one half the distance between the top pipe/rail and the ground 
c) Weaving the insulated wire  as close to the ground as possible  
The question being which alternative is theoretically/technically the best. 
Thanx
73 de Jordan ve7jjd





Re: Improved 1 kHz DSP Audio in New CC Skywave SSB Model

Gary DeBock
 

Hi Guy,

Thanks for your comments, and you certainly raise some interesting questions (especially considering your extensive experience in premium IF filter modifications for Ultralight radios like the Eton E100, etc.).

<<<   These inexpensive radios with DSP filtering do not have the processor power to get anywhere close to the proverbial "brick wall" shape factor of SDR radios (and I wouldn't expect them to). With that in mind we could just be hearing more audio frequencies as a result of a modest slope to the filter edges. I recall seeing some measured filter plots of one of these SiLabs-powered DSP radios that a hobbyist posted (possibly from an Eton Satellit) and three of the voice bandw idth filters were actually quite close to one another in actual measured width, and the filter slopes were pedestrian.   >>>

Well, there certainly is some circumstantial evidence of improved audio fidelity combined with equivalent splatter rejection in the new CC Skywave SSB model in the 1 kHz DSP setting, but to be honest I haven't yet had the time to run the detailed daytime DX tests necessary to confirm this (such as the 700 kHz Airway Heights station next to 710-KIRO, and the 860-Portland station next to local 850-KHHO). I visited Kona, Hawaii in April, also, and made lots of DX station MP3's with the original CC Skywave model in its 1 kHz setting. I'll need to check those to see if they were somewhat more splatter-free than the recordings made last month of the same DX stations, but there's no doubt that the audio fidelity of the DX recordings was greatly improved. One thing that I definitely noticed last month in Kona was the first appearance of 3 kHz heterodynes on DX station frequencies like 837, 1017 and 1593. After the original recordings were made I needed to run the MP3's through the Audacity program to remove the 3 kHz heterodynes-- something that I've never needed to do with any other Ultralight radio. So as far as 'high fidelity," maybe that is somewhat of a breakthrough? :-)

Hawaii certainly has its share of troublesome MW splatter generators, so it should be quite easy to compare the splatter in the recordings from April and December. Off hand the only Pacific island DU that was splatter-free in April but covered by splatter last month was 558-Fiji, which never showed up at all because of some Maui splatter from 550. Some of the "big gun" TP frequencies here on the west coast are hopeless in Kona because of Hawaii splatter-- such as 594, 693, 1566, etc. 

73, Gary (across town, still going through Kona MP3's)   

    


-----Original Message-----
From: dx@... [ultralightdx]
To: ultralightdx
Sent: Wed, Jan 3, 2018 8:28 pm
Subject: [ultralightdx] Re: Improved 1 kHz DSP Audio in New CC Skywave SSB Model

 
Hi Gary,

The recordings from the Skywave SSB sound very nice in 1 kHz bandwidth, something I've noticed in my Skywave SSB also.

Do you feel the adjacent channel rejection is as good with the SSB model using its 1 kHz filtering? Or, I wonder if it is spec'd at plus/minus 1 kHz rather than 1 kHz total width? It just sounds to me like there's more audio recovered than I would expect from a 1 kHz narrow filter.

These inexpensive radios with DSP filtering do not have the processor power to get anywhere close to the proverbial "brick wall" shape factor of SDR radios (and I wouldn't expect them to). With that in mind we could just be hearing more audio frequencies as a result of a modest slope to the filter edges. I recall seeing some measured filter plots of one of these SiLabs-powered DSP radios that a hobbyist posted (possibly from an Eton Satellit) and three of the voice bandw idth filters were actually quite close to one another in actual measured width, and the filter slopes were pedestrian.

On the other hand, I wouldn't expect the Skywave SSB model to have a poorer performing 1 kHz filter (letting in more frequencies at the filter edges); maybe the audio gain stages and AGC are simply better in the SSB radio?

I hope someone with more insight into these little DSP marvels than myself can step in to provide more information.

I'm not complaining, as the result certainly does sound great from a signal intelligibility standpoint, Gary! My main question would be--does rejection of nearby domestic channels seem as good as with the non-SSB model?

73,

Guy Atkins
Puyallup, WA


Beveridge Antennas

Jordan Dobrikin <jjdobrikin@...>
 


Hi 
I am looking for information comment advice and/or assistance in designing and building Receive Only long wire/Beveridge antennas at my new QTH. It is a combination 2 3 & 4 story wood frame construction Senior Citizens Apartment/Assisted complex surrounded by a chain-link fence and adjacent to a large open undeveloped Lot covered in grass weeds and light underbrush. 

I am considering several mechanical types of long wires Beveridges and "Baby Beverages".  
The most correct would be PVC pipe extensions of the fenceposts to support the wire 2 to 3 feet above the top rail of the fence. However, that would somewhat obtrusive and costly.  

I am considering stealth/semi-stealth antennas the simplest laying out wire on the ground on the adjacent Lot.  
 
An alternative is to use the chain link fence for mechanical support of insulated wire 
a) Using zip ties to attach the wire to the top pipe/rail 
b) Weaving the insulated wire one half the distance between the top pipe/rail and the ground 
c) Weaving the insulated wire  as close to the ground as possible  
The question being which alternative is theoretically/technically the best. 
Thanx
73 de Jordan ve7jjd


Re: Lithium Batteries

Paul S. in CT
 

One type of cell not mentioned is Lithium-Iron-Phosphate (LiFePO). These are safer than Li-Ion Colbalt types (the "regular" Li-Ion) as they survive abusive charging methods better. Lithium-Polymer (LiPoly) cells that are coming into use have almost no container, and expand rather greatly with improper charging (so-called "pillow effect").

LiFePO cells are rated at 3.0 Volts with peak open-circuit voltage of 3.2. Thus they make excellent replacement for TWO Alkaline AA cells. Capacity is low on these compared to li-Ion types. An AA cell Alkaline (Primary) has about 2500mahr, a Li-Ion (Recharge 3.7V) about 1200mahr, and the LiFePO (Recharge) about 700mahr. Apparently, from what I read, the Li-Poly (3.6V Recharge) cells fall in between 700 and 1200mahr.

All Lithium rechargeables MUST have a special circuit to properly charge them and protect from abuse (over-voltage) and some cells themselves have a limiter to prevent discharge below a certain voltage.

As for branding of Alkaline cells, I too have heard of "knock-off" cells. MHO is that you are not likely to find them in your local store(s), but rather in places like Amazon, eBay, and AliExpress. /MHO

Regards
Paul S. in CT


Re: Improved 1 kHz DSP Audio in New CC Skywave SSB Model

Guy Atkins
 

Hi Gary,

The recordings from the Skywave SSB sound very nice in 1 kHz bandwidth, something I've noticed in my Skywave SSB also.

Do you feel the adjacent channel rejection is as good with the SSB model using its 1 kHz filtering? Or, I wonder if it is spec'd at plus/minus 1 kHz rather than 1 kHz total width? It just sounds to me like there's more audio recovered than I would expect from a 1 kHz narrow filter.

These inexpensive radios with DSP filtering do not have the processor power to get anywhere close to the proverbial "brick wall" shape factor of SDR radios (and I wouldn't expect them to). With that in mind we could just be hearing more audio frequencies as a result of a modest slope to the filter edges. I recall seeing some measured filter plots of one of these SiLabs-powered DSP radios that a hobbyist posted (possibly from an Eton Satellit) and three of the voice bandwidth filters were actually quite close to one another in actual measured width, and the filter slopes were pedestrian.

On the other hand, I wouldn't expect the Skywave SSB model to have a poorer performing 1 kHz filter (letting in more frequencies at the filter edges); maybe the audio gain stages and AGC are simply better in the SSB radio?

I hope someone with more insight into these little DSP marvels than myself can step in to provide more information.

I'm not complaining, as the result certainly does sound great from a signal intelligibility standpoint, Gary! My main question would be--does rejection of nearby domestic channels seem as good as with the non-SSB model?

73,

Guy Atkins
Puyallup, WA

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