From: D1028Gary@...
Subject: Re: [ultralightdx] Re: G8 vs CR-1100 preliminary AM BCB report-FARMERIK
To: ultralightdx@...
Date: Sunday, January 3, 2010, 3:39 PM

Hello Richard,

 

Yes, you are absolutely correct.

 

The radio is the new Redsun RP007, a waterproofed, shock-resistant AM-FM-SW portable radio apparently designed by Redsun according to a demanding order by the Russian military. The radio is specifically designed to withstand severe weather conditions, so that a special agent out in the field could receive radio communication despite rain, severe cold, or even dropping the radio in a river (!).

 

The original plan was to report to the group about the awesome survival capabilities of this new portable radio (which actually has very good AM reception, similar to an RP2100 with better IF filtering), but for some reason Redsun never found a seller to market the radio on eBay for export (the Chinese domestic price is around $140 on Taobao), so until an eBay seller offers the model for sale, I don't have any source to recommend to potential purchasers. To make this story even more bizarre, the anonymous eBay seller who sent me this free radio (which he received free from Redsun) is now no longer selling on eBay, having gone through a stretch of poor health, which caused delayed radio shipments to send his feedback rating from 100% down to 97%.

 

The entire episode is like something straight out of a spy thriller. So my free Redsun RP007 (despite its awesome survival construction) now still awaits a purchasing source for North American hobbyists, before I can post a full review on it.

 

73, Gary DeBock       

 

In a message dated 1/3/2010 1:31:27 P.M. Pacific Standard Time, lrdheat@... writes:

 

Gary,   I think that you mentioned awhile back that a company was letting you test a new, possibly great mw radio (doesn't matter to me if it is not a ulr...). Is there reason for us to hope that a new, great radio is in the offing???   Happy New Year!   Heatwave    --- On Sat, 1/2/10, D1028Gary@aol. com wrote: From: D1028Gary@aol. com Subject: Re: [ultralightdx] Re: G8 vs CR-1100 preliminary AM BCB report-FARMERIK To: ultralightdx@ yahoogroups. com Date: Saturday, January 2, 2010, 11:05 PM   Hello Farmerik,   All of the radios you mentioned (G8, PL-380, CR-1110 and PL-600) are on hand here, in this overcrowded shack.   The CR-1110 is a rather odd bird that has far better AM sensitivity on the high frequencies (especially the X band) than on the middle and low band. It was tested extensively against an aligned Sony ICF-S5W on all frequencies from 530-1700 kHz, and was found inferior in sensitivity to that classic model on most AM frequencies, but clearly superior on the X band. It also did not suffer from the ICF-S5W's severe image reception issue, of course.   I did a mini-review of the CR-1100 back in June, which may be of interest to you. Some of the information is dated (such as the praise of the PL-300WT, the only DSP model available at the time), but the rest should give you detailed impressions on the model. Hope you enjoy it!   73 and Have Fun,  Gary   Hello All, Very impressed with the performance of the new Tecsun PL-300WT DSP-enhanced Ultralight radio on medium-wave, it was a natural decision to place an order with Amazon.com for the new full-sized Tecsun CR-1100 AM-FM portable, which uses the same innovative Si430/31 DSP chip from Silicon Labs. Today my new CR-1100 portable arrived from Kaito Electronics after a 4-day delay, and payment of $69.99 plus $13.00 shipping (by USPS Priority Mail). The CR-1100 is strictly a Chinese-market portable, to the extent that all of the controls are labeled only in Chinese. Despite this, Kaito has provided a very basic (and poorly translated) English manual, as well as the standard and far more thorough Chinese manual. The AM frequency steps have also been reprogrammed to 10 kHz, matching the North American market. Immediately after arrival, the radio's out-of-the-box AM performance was tested against a fully aligned Sony ICF-S5W portable (which has had the frequency coverage extended to 1700 kHz). The comparison of these two radios proved to be very interesting, and showed that while the CR-1100 has some good DXing potential on AM, it also has some puzzling shortcomings. In comparison to the PL-300WT's sharp DSP-enhanced selectivity, the CR-1100 had a tough time going up against the ICF-S5W, with its common 455 kHz Murata filter. Local slop on the CR-1100 was more troublesome than on the PL-300WT, making it seem like Tecsun programmed the DSP chip to provide a wider selectivity setting on this music-oriented receiver. The ICF-S5W was able to weakly receive KPQ-560 in the null of semi-local KVI-570 in the early afternoon, while the CR-1100 could only produce KVI splatter. Low-band sensitivity on the CR-1100 was very good, but not quite up to the class-leading ICF-S5W standard. Although the CR-1100's low-band sensitivity will match that of the PL-300WT, unlike the PL-300WT, the CR-1100 cannot tune in 1 kHz steps, making it impossible to chase TP's on the 9 kHz splits. The CR-1100 versus ICF-S5W contest became much more competitive on the high band, however, and on the X-band the new Tecsun was clearly far more sensitive than the classic Sony portable. In fact, the CR-1100 sets a new standard for X-band sensitivity among portables, having weak signal performance never experienced in extensive testing here. Weak fringe stations that were barely audible on the ICF-S5W had solid audio on the Tecsun. Also notable in the CR-1100 was the complete freedom from image reception of local stations, a major shortcoming of the classic ICF-S5W. The Sony's image reception detracts greatly from its otherwise stellar performance, but the Tecsun DSP chip appears to have solved the problem entirely. After the out-of-the-box performance test, the CR-1100 was disassembled to check the loopstick construction, and the possibility of alignment. Both the PL-300WT and CR-1100 were designed to have a "no alignment" RF system, in which the DSP chip ensures maximum performance without loopstick peaking, or adjustment of a 1400 kHz trimmer. In the CR-1100, there is a 4.25" x .36" single-coil loopstick in the middle of the cabinet, which seems rather odd because of the extensive cabinet space on both sides which would allow placement of a much longer ferrite bar, if desired. Alignment was attempted by shifting the coil, but this had no effect on the CR-1100's sensitivity on any AM frequency. Apparently DXers will need to accept the CR-1100's sensitivity as delivered, unless they wish to transplant a larger ferrite bar with a coil of equal inductance (which is certainly possible with all the extra cabinet space). The CR-1100 also has a sensitive FM section, although again, for some unknown reason it seemed slightly less sensitive than that of the PL-300WT. Perhaps there is a greater impedance mismatch with the CR-1100's short whip antenna, but in any case the PL-300WT Ultralight can receive more weak FM fringe stations here than the CR-1100. The CR-1100 has a large music-oriented speaker and excellent audio, with analog tone and volume control knobs. The 8-ohm speaker has a 1-watt rated output. The radio also has 300 memories, and various digital tuning capabilities. It operates on 4 "D" batteries, and comes in an attractive black-brown cabinet. It is available from Amazon.com (via Kaito Electronics) for $69.99 plus $13.00 shipping. So after the full evaluation, what would be the CR-1100 verdict for a dedicated medium-wave DXer? If you are a domestic DXer that concentrates on the upper frequencies (especially the X-Band), the new CR-1100 would be tough to beat. Its upper-band sensitivity (and generally good selectivity) is likely to set a new standard for contemporary portables. Urban DXers will appreciate the complete freedom from image reception, and general freedom from spurious products. Hobbyists who enjoy music reception will not be disappointed in the CR-1100's audio qualities. However, if you wish to chase transoceanic DX, or wish to experience the maximum potential of the exciting new Silicon Labs DSP chip, my recommendation would be to pass on the CR-1100-- and go for the new PL-300WT Ultralight model. Its 1 kHz tuning ability and stellar selectivity (plus superior FM sensitivity) make it the obvious choice for most medium-wave DXers. 73 and Best Wishes, Gary DeBock (in Puyallup, WA)  farmerik@cox. net writes:   OK, now I get it. Sort of like the audio version of the screen break-up on digital video. I can see why it would be a problem for really weak signal DXing, however on my G8 I don't think I will miss any station strong enough to actually listen to. Both the G8 and CR-1100 hear weak stations with less noise and interference than my analog radios, but miss all the really weak signals entirely. The CR-1100 is significantly more sensitive and has less noise on its weak stations though. Anyone have a PL-380 AND a CR-1100 to compare? My new PL-600 seems MUCH more sensitive than the CR-1100. - FARMERIK --- In ultralightdx@ yahoogroups. com, Richard Berler wrote: > > The soft mute occurs when tuned exactly on frequency on weak signals that vary between s/n's of 0, and s/n's that rise above zero...instead of a smooth rise or fall in the audible signal, the signal sounds like it is flickering. The set, if soft mute is the default mode (as it is on the G8 and PL-310), will semi mute the signal of a station that falls below (or rises above) a certain threshold of signal strength, resulting in the flickering of the audible signal. >   > Heatwave > > --- On Sat, 1/2/10, farmerik wrote: > > > From: farmerik > Subject: [ultralightdx] Re: G8 vs CR-1100 preliminary AM BCB report-FARMERIK > To: ultralightdx@ yahoogroups. com > Date: Saturday, January 2, 2010, 9:49 AM > > >   > > > > > I used to use WICC as a test for a good radio in the daytime. It is much closer to Westport than I am in the Northeast of CT, while Westport and Naugatuck [WICC] are in the Southwest part of the state. Since you used to live in the area, I'll mention some call letters next time. > > Maybe I need some help understanding exactly what the dreaded soft mute sounds like. Is it only a problem when tuned one or two Kc. off? Or is it the mute which happens before you couple an external loop, and you have to change frequency, and come back after the loop is in place? Maybe something else entirely? - FARMERIK > > --- In ultralightdx@ yahoogroups. com, Richard Berler wrote: > > > > Thanks! > >   > > Also, check to see if there is a pumping on marginal-weak daytime signals (the dreaded soft mute). > >   > > I used to live in Westport, CT. From there, I needed a good radio to get WBZ and WPRO during the daytime, and to get WCAU, KYW, and WFIL?(560) from Philly. > >   > > Heatwave > > Streets of Laredo, TX! > >   > > --- On Fri, 1/1/10, farmerik wrote: > > > > > > From: farmerik > > Subject: [ultralightdx] Re: G8 vs CR-1100 preliminary AM BCB report-FARMERIK > > To: ultralightdx@ yahoogroups. com > > Date: Friday, January 1, 2010, 7:21 PM > > > > > >   > > > > > > > > I'll see what I can do. I usually don't listen in the daytime.- FARMERIK > > > > --- In ultralightdx@ yahoogroups. com, Richard Berler wrote: > > > > > > Happy New Year! > > >   > > > Can you do some mid-day testing, and post your observations? > > >   > > > Thanks! > > >   > > > Heatwave > > > > > > --- On Thu, 12/31/09, farmerik wrote: > > > > > > > > > From: farmerik > > > Subject: [ultralightdx] G8 vs CR-1100 preliminary AM BCB report-FARMERIK > > > To: ultralightdx@ yahoogroups. com > > > Date: Thursday, December 31, 2009, 11:31 PM > > > > > > > > >   > > > > > > > > > > > > I've had the G8 for a couple months, since joining here, but just got my CR-1100 today. Both have the same DSP chip I believe. The CR only tunes in 10 Kc. steps on the AM BCB, but I believe it can be programed for 9 Kc. steps too.[You can not 'slope tune' it off a Kc. or two to escape an adjacent much stronger station.] > > > > > > The CR-1100 is rated by Tecsun at 0.5mv/M with its larger ferrite and the G8 is listed as 1mv/M. The CR-1100 is not really so much different than a modified DSP ULR with larger ferrite, but I don't think it qualifies for competition. > > > > > > I placed the two radios side by side, facing the same direction, running both on good alkaline batteries. I tuned three ten 'channel' bands, 700-790, 1000-1090 and 1500-1590, and took notes on each station I heard. I'll summarize here. The CR is noticeably better on about 50% of the frequencies, and about 1/3rd of those are substantial improvements. I got stations on all but 6 of the 30 frequencies on both radios, so it is a good night here in Connecticut. > > > > > > As expected, the audio bandwidth on the CR sounds noticeably wider, but what I didn't expect is that when ever there is back round noise, or a second weak station is also heard, it is much quieter on the CR. I expected wider selectivity to hear more noise and other stations not less. The narrower G8 bandwidth seems to hurt, NOT help with interference. > > > > > > Also, I looked at the meters for dBa and s/n. Both numbers scrolled all the time on strong and weak stations. The CR had +5 to +10 more units on the dBu scale on average, and sometimes the differences were much greater. The G8 ran +10 to +15 units on the s/n read out. I don't know what to make of that, but probably they are not 'calibrated' or 'standardized' , so it does not mean a thing. If anyone can explain it, I'm all ears. > > > > > > I tried the TERK with both radios, and as before with the G8, it can lower back round noise,but it does not seem to ever dig a weak station out of noise like it does on a cheap portable. > > > > > > -FARMERIK > > > > > > Reply to sender | Reply to group Messages in this topic (8) .