On Tue, Mar 21, 2023 at 06:42 AM, radiojayallen wrote:

I've had my D-109 for  few days now and my initial reponse is overwhelmingly positive. Comparing it with my original version D-808 the D-109 seems slightly more sensitive and has slightly fuller audio and its SD card reader allows scanning within tracks which many such players don't. Even though it lacks SSB I've got to say that for the price it seems like it's going to be hard to beat.

Jay

Thanks Jay,

The new D-109 has received positive reviews from almost every AM-DXer, and the radio has an unsurpassed "fun factor" with its combination of relatively high fidelity audio into a powerful 5 watt speaker.

Upon initial review of the D-109 I was much like Les Rayburn-- very impressed with its AM-DXing capabilities but desiring a more sensitive loopstick for even greater AM-DXing performance. Although the model is a little tricky for loopstick transplants because of the hash-emitting digital display, eventually I found a new loopstick position which avoids the hash while transforming the model into a dream AM-DXing portable.

73, Gary DeBock (in Puyallup, WA, USA)

On Tue, Mar 21, 2023 at 05:13 AM, Michael Schuster wrote:

The underlying cause is the omission of an audio preamp (necessary to match the relatively low DSP output).
To compensate they were running the audio amp at an extremely high gain setting where its SNR is poor - hence the background noise.
Unfortunately it would appear that, in a counterproductive attempt to fix that cheaply, they simply turned down the gain!

--mike

Thanks Mike,

I think you are exactly right about this. A "new model" D-808 seems to retain the background noise while reducing the overall gain of the audio amplifier, thereby making the model much less effective in chasing very weak AM-DX stations. Especially for weak-signal DXers, that sort of change is a major drawback.

It's also worth remembering that most of XHDATA's consumer market in China probably doesn't care much about weak signal DXing, so it's unrealistic to always expect them to prioritize our wishes. A bright spot for DXers is the new XHDATA D-109 model, which seems to have improvements in the SNR as well as the full range of DSP filtering options, a powerful speaker and a decent audio amp.

73, Gary DeBock (in Puyallup, WA, USA)

I've had my D-109 for  few days now and my initial reponse is overwhelmingly positive. Comparing it with my original version D-808 the D-109 seems slightly more sensitive and has slightly fuller audio and its SD card reader allows scanning within tracks which many such players don't. Even though it lacks SSB I've got to say that for the price it seems like it's going to be hard to beat.

Jay

On Mon, Mar 20, 2023 at 04:47 PM, Gary DeBock wrote:

In addition to the USB cable plug change, the RF boards in the old and new D-808 models are entirely different (see photos). The biggest change is a major drop off in the audio amplifier power in the new models, which negatively affects reception of very weak AM-DX stations. Maxing out the volume control in the new models results in significantly lower volume than in the the original D-808 models.

Thanks Gary!


This group will recall that the original hardware of this family of "808" radios (XHDATA/Sihuadon/Deshibo/Digitech) all suffer from a high background audio noise floor, most apparent at low volume.
It is also impedance-dependent, so the problem will be more or less apparent depending on what headphones you attach.

The underlying cause is the omission of an audio preamp (necessary to match the relatively low DSP output).
To compensate they were running the audio amp at an extremely high gain setting where its SNR is poor - hence the background noise.
Unfortunately it would appear that, in a counterproductive attempt to fix that cheaply, they simply turned down the gain!

--mike

Op 20/03/2023 om 23:20 schreef Gary DeBock via groups.io:

Many of the Chinese companies ...

We haven't heard that of the far west?

Many of the Chinese companies make equipment changes to increase

profits, but they never tell customers about the negative changes that they make.


Marc
--
The "Penguin" has arrived - and he's not going away - ever.
For former Apple users: Xubuntu.org (menu's up left)
For former Windows users: Lubuntu.org (menu's down left)

The following files and folders have been uploaded to the Files area of the main@UltralightDX.groups.io group.

• /LTDXProject_March2023.pdf
• /LTDXProject_March2023_Blank.pdf

By: Paul Blundell <tanger32au@...>

Description:
LongTerm DXing Project Log Files

Hi all.

I have just uploaded two example log files for my LongTerm DXing Project, one is an example with my stations listed and the second has this area blank, to be filled in with the stations you wish to log.

The idea of this is to log the same 10 stations at various times and in various location. I use a scale of 0 to 5 to rate the signal, you can use whatever scale or system works best for you.

Paul

On Mon, Mar 20, 2023 at 03:07 PM, <chevargasluis@...> wrote:

Qué bueno que lo mencionas Gary. pensaba comprar uno de esos pero en esas nuevas condiciones ya no lo haré. Generalmente cuando cambian algo en el diseño de un aparato es para empeorarlo no para mejorarlo 

Gracias Chevargasluis,

You are correct. Many of the Chinese companies make equipment changes to increase profits, but they never tell customers about the negative changes that they make.

73, Gary DeBock (in Puyallup, WA, USA)

Based on very favorable reports from Les and others I decided to order several new XHDATA D-109 models for testing and experiments, despite the fact that there is currently no North American supply source. The model is only available from China, with the current lowest price (including shipping) of $39.99 from the eBay vendor "liulituan2014."

Like Les, my impression is that this LW-AM-FM-SW portable delivers a lot of performance for the price. The model has the full range of DSP filtering choices from the internal Silicon Labs' Si4734 DSP chip, and in combination with a reasonably powerful audio amp, the superb 5 watt speaker really makes DXing a pleasure, especially in noisy environments. The radio has Bluetooth and MP3 playback capability, and the relatively powerful speaker enhances the value of these additional features. The stock 70mm loopstick does a reasonable job in tracking down AM-DX stations in comparison with its competition (Radiwow R-108, Tecsun PL-330, etc.), although there is no SSB capability like in the XHDATA D-808 and Tecsun PL-330 models. Overall the stock model does a great job for the price, especially considering the powerful battery, the Bluetooth and MP3 playback capability (with relatively high fidelity audio) and competitive AM, FM and Shortwave DXing performance.

Les had asked specifically about an enhanced loopstick for this model, and of course I was highly motivated to try such an experiment. Upon disassembly I noticed that the stock loopstick was in a strange position at the bottom of the cabinet-- and as far away as possible from the digital display. Usually, when a manufacturer does this it is for a good reason-- the digital display noise would otherwise interfere with the loopstick's reception. In the D-109's case the wide separation of the two components does allow AM-DX reception without digital display noise (unless the user touches his palm to the display), but mounting an enhanced loopstick at the bottom of the cabinet just wouldn't work. I went ahead and did the enhanced loopstick transplant in the D-109 anyway, which was a little trickier than the same procedure in the XHDATA D-808 because the R-109 really isn't engineered for easy disassembly. Upon mounting the enhanced 7.5 inch loopstick in the usual position (see photo) my apprehensions were confirmed when moderate digital noise showed up on all frequencies from 530-1700 kHz. As expected the enhanced loopstick did provide a tremendous boost in the R-109's AM-DXing sensitivity, but the digital hash issue was unacceptable, in my opinion. Most other Ultralight and portable models do not have this digital hash problem, and are much better candidates for an enhanced loopstick transplant.

Since I had already done the D-109 loopstick transplant I wanted to finish up with a hot-performing AM-DX model which was totally free of any digital hash. The only solution was to relocate the enhanced loopstick farther away from the digital display on the left side of the orange frame, as shown in the photo. This antenna position allowed the R-109 to chase AM-DX with superb sensitivity and noise-free reception, making it fully equal in performance to a "Supercharged" XHDATA D-808 model. Although the side-mounted loopstick is less than optimum for aesthetic and other reasons, it does transform this R-109 model into a paragon of AM-DXing prowess.

Best of DX,
Gary DeBock (in Puyallup, WA, USA)
Ex-Navy Sonar Technician

Qué bueno que lo mencionas Gary. pensaba comprar uno de esos pero en esas nuevas condiciones ya no lo haré. Generalmente cuando cambian algo en el diseño de un aparato es para empeorarlo no para mejorarlo 

On Mon, Mar 20, 2023 at 06:02 AM, Michael Schuster wrote:

I've seen mention elsewhere of a design change in the Siduadon-brand version of the D-808 which has a USB-C charging port.

Michael, Paul and All,

There has been a major redesign in new D-808 models, which I first noticed while doing a loopstick transplant on a new Sihuadon D-808 model two weeks ago.

In addition to the USB cable plug change, the RF boards in the old and new D-808 models are entirely different (see photos). The biggest change is a major drop off in the audio amplifier power in the new models, which negatively affects reception of very weak AM-DX stations. Maxing out the volume control in the new models results in significantly lower volume than in the the original D-808 models. In addition, you must short-press the Power switch to turn the new models on or off, unlike in the original D-808 models. If you press the Power switch on the new models and hold it down, the radio will beep, but nothing happens. I have personally verified that the Si4735 DSP chip is still used in the new D-808 models, so RF reception is still unchanged-- only the audio amp is weaker. There are probably other changes in the new models, which will be discovered after further investigation.

What isn't clear at this point is whether this new D-808 version will only be for Sihuadon D-808 models, or for all D-808 models from now on. My strong impression is that all D-808's will made this way from now on, since the circuit boards in the new version are stamped "D-808," and don't mention "Sihuadon," or "XHDATA." I have ordered a new XHDATA D-808 to find this out, and should receive it within a week. As for the weaker audio amp in new D-808 models, XHDATA certainly won't mention anything about this, so bear this in mind if you are an AM-DXer who typically searches for very weak DX stations.

73 and Good DX,
Gary DeBock (in Puyallup, WA, USA)

I've seen mention elsewhere of a design change in the Siduadon-brand version of the D-808 which has a USB-C charging port.

Have you tried turning off the LCD display once tuned to the selected frequency?

CCrane obviously knew about internally generated noise from the very start, that is why the option to turn off the display exists.

I am used to seeing unit to unit differeces in general but my experience seems to indicate that with the major manufacturers, modern designs seem to have reduced such variability. Of coure you can still get a bad unit from anyone but in general I see fewer differences unit to unit within a production run than, say, 20 years ago.

And it has also become more common for some companies to make minor revisions form one production run to another and often without any indication this has happened...we
see that all the time.

Jay

Hi Gary, Jay and the group,
Well, could be that I got a faulty unit, I don't know. Mine was sent from Crane shop in the USA and it is not easy to return it back and get a new one. It was much easier with an faulty ETON Elite Traveler unit but as it was purchased via Amazon and they manage very good and quick return shipment.

I will carefully check again the Crane CC Pocket against the others but it seems a receiver with a lack of screening. It is the unit itself which is noisy because of the LCD screen but also with the environment QRM if any. Even in the middle of nowhere the internal noise is quite evident in every empty channel. It does not affect to the sensitivity as it is able to hear, but with no success.

Something that I am starting to think is about the lack of quality control. That was the case with my ETON Elite Traveller. The second unit seemed a totally different radio and I am satisfied with it, even when other models I own could be better as DXing ULR. When there is a lack of quality control, are testings we do valid at all? Imagine Jay your test Crane/Sangean. You start with a (partially) faulty unit and the results are "A". But if you order a second one and repeat testing procedures, result is "B", and even worst... Who can be sure than a third unit does not give a "C" result. This is a serious matter, I reckon!

Perhaps the brilliant comparisons we were used to (WRTH, JayAllen, Universal Radio and similars...) were perfect in our beloved old era, when a receiver was something to be proud to be created and offered. Now, with the Chinese steamroller, radios are in an industrial age where everything can be replaced easily don't even thinking in customers's comments or opinions. Then, how can we trust in a new released radio?
73 de J  

In fact the CC Pocket has rcently been revised with some new features and I am working on a comparative review of it along with the previous version and the Sangean DT-800...I hope to post it soon.

However I did compare the original CC Pocket with the Sangean DT-400 and here are some coomments from that artcvle:




Jay