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Re: [IRCA] Hot-Rodded SSB Travel Portables-- Fight to the Finish (of the MW Band)

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 Gary,
Thanks for the comparison between the SSb SkyWave and the XHData radio. I always enjoy reading about your efforts to tweak small, travel friendly portables for more DXing performance. BTW the Ebay seller will be having a sale on these radios for ~$77. That seems like a pretty good price.
Here's the link:

XHDATA D 808 Portable Digital Radio FM stereo/ SW / MW / LW SSB AIR RDS Multi Band Radio Speaker with LCD Display Alarm Clock-in Radio from Consumer Electronics on Aliexpress.com | Alibaba Group


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XHDATA D 808 Portable Digital Radio FM stereo/ SW / MW / LW SSB AIR RDS ...

Cheap radio fm stereo, Buy Quality fm stereo directly from China portable digital radio Suppliers: XHDATA D-808 ...
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73,
Craig Barnes
    On Tuesday, June 12, 2018, 3:00:43 PM MDT, Gary DeBock <d1028gary@xxxxxxxxxxx> wrote:  
 
 <<< But if we are going to compare radios via audio files, why not take the simple step of adjusting the recorded files to have the sane volume levels? This really has nothing to do with cliffside DXing etc.
And the "audio processing" I did was just simple volume adjustment. >>>

Chuck,

If an audio amp wimps out on a weak signal during live DXing and you are depending on the identity of that weak signal to make a propagation assessment during a limited-time sunrise opening, the failure of that amp to deliver sufficient audio can dramatically affect your DXing results for the entire morning. The first step in live DXing is to determine which way propagation is trending (NZ, Oz, or both, in the case of the cliff)), so that you know which other frequencies to check during your limited time.

The posted audio files for the two receivers were entirely accurate, since they reflect the quirk of the CC Skywave's audio amp to wimp out on extremely weak signals. Equalizing the audio after the fact would have hidden this quirk from potential purchasers, including live DXers who need to be aware of this serious shortcoming in the Skywave's design.

Gary


> On June 12, 2018 at 12:15 PM Chuck Hutton <charlesh3@xxxxxxx> wrote:
> 
>  But if we are going to compare radios via audio files, why not take the simple step of adjusting the recorded files to have the sane volume levels? This really has nothing to do with cliffside DXing etc.
> 
>Â Â And the "audio processing" I did was just simple volume adjustment.
> 
>Â Â Chuck
> 
> 
> 
>Â Â ---------------------------------------------
>Â Â From: Gary DeBock <d1028gary@xxxxxxxxxxx>
>Â Â Sent: Monday, June 11, 2018 8:25 PM
>Â Â To: Chuck Hutton; Mailing list for the International Radio Club of America
>Â Â Subject: Re: [IRCA] Hot-Rodded SSB Travel Portables-- Fight to the Finish (of the MW Band)
>Â Â Â 
>Â Â Chuck,
> 
>Â Â Yes, after-the-fact audio processing can often do wonders in improving marginal signals.
> 
>Â Â Unfortunately, when a live DXer is in a noisy location and a wimpy audio amp bails out early, there could be a sudden temptation to throw it off of a 500 foot cliff.
> 
>Â Â Gary
> 
> 
>Â Â Â Â > > On June 11, 2018 at 6:09 PM Chuck Hutton <charlesh3@xxxxxxx> wrote:
> > 
> >Â Â Â Â After normalizing the audio levels of both recordings, I can not hear any difference at all.
> > 
> >Â Â Â Â Normalizing in this case resulted in a fairly small increase on gain for the first 19 seconds.
> > 
> >Â Â Â Â Chuck
> > 
> > 
> > 
> >Â Â Â Â ---------------------------------------------
> >Â Â Â Â From: IRCA <irca-bounces@xxxxxxxxxxxxxxxx> on behalf of Gary DeBock <d1028gary@xxxxxxxxxxx>
> >Â Â Â Â Sent: Monday, June 11, 2018 5:17 PM
> >Â Â Â Â To: America, Mailing
> >Â Â Â Â Subject: [IRCA] Hot-Rodded SSB Travel Portables-- Fight to the Finish (of the MW Band)
> >Â Â Â Â Â 
> >       Recently the new XHDATA D-808 AM-LW-FM-SW-AIR-SSB portable has finally become available to North American purchasers, with a couple of eBay sellers in China offering the innovative Si4735-chip based model for around $112, plus $10 shipping. As reported in previous posts, the new model delivers a lot of performance for the price, offering the best AM-DXing sensitivity for any portable in its size range, along with superb FM-DXing sensitivity. A high resolution photo of the new model is posted at https://dreamcrafts.box.com/s/82se0nphymzayz1vw4fk8vnkia11xedm https://dreamcrafts.box.com/s/82se0nphymzayz1vw4fk8vnkia11xedm
> > 
> >Â Â Â Â Â Â Â The C.Crane Skywave SSB model is also a great performer for the size, although its relatively short loopstick (66mm vs 96mm) causes it to fall short of the D-808 in AM sensitivity, as well as in FM sensitivity. At a $169.99 list price (plus shipping), it also falls quite a bit short of the new D-808 in affordability. It performed very well in my recent DXpedition to the Cook Islands, but almost any portable would probably perform like a champion in such an enhanced environment. In any case, I was curious how the CC Skywave SSB model and XHDATA D-808 would stack up against each other with exactly the same Medium Wave antenna-- a 7.5 inch transplanted loopstick (originally designed for the Tecsun PL-380 model).
> > 
> >       After a new XHDATA D-808 model was "supercharged" with one of these high-performance loopsticks (a very easy process to perform, in comparison to the same, nerve-wracking operation on the ultra-compact Skywave) https://dreamcrafts.box.com/s/vk26lkhhu77q8buzuaido03fmy5s7xst https://dreamcrafts.box.com/s/vk26lkhhu77q8buzuaido03fmy5s7xst  , the two hot-rodded portables assembled for a high-noon Shootout in the reception of two ultra-weak daytime DX stations-- the SeaTac airport TIS on 530 kHz (15 watts at 17 miles) and the 1700-City of Auburn TIS (15 watts at 11 miles). A photo of the two contestants in the high noon sun is posted at https://dreamcrafts.box.com/s/2vbsnhbbz5pyq45mki4cnbz45v4l96jq https://dreamcrafts.box.com/s/2vbsnhbbz5pyq45mki4cnbz45v4l96jq
> > 
> >Â Â Â Â Â Â Â Both models needed to absolutely max out their volume levels in order to receive these ultra-weak stations. The SeaTac Airport TIS was received by the 7.5" loopstick CC Skywave SSB model for the first 19 seconds in the following MP3, and the new 7.5" loopstick XHDATA D-808 model received the same very weak station for the next 30 seconds (recorded within a few seconds of each other)Â https://dreamcrafts.box.com/s/f3otu59k92e7rfletc093n9uehf0pawl https://dreamcrafts.box.com/s/f3otu59k92e7rfletc093n9uehf0pawl
> > 
> >       The next test was in the reception of the 1700-City of Auburn TIS station (another super-weak station). Once again, both models needed to absolutely max out their volume levels. The 7.5" loopstick CC Skywave SSB received the station for the first 22 seconds, while the 7.5" loopstick XHDATA D-808 received it for the next 32 seconds https://dreamcrafts.box.com/s/mucugek9f4rqpnb3us6nlpb6nbp5iqdc https://dreamcrafts.box.com/s/mucugek9f4rqpnb3us6nlpb6nbp5iqdc
> > 
> >Â Â Â Â Â Â Â The overall judgement (in my opinion) was that although both models were fairly competitive in actual signal quality delivered, the CC Skywave definitely suffers because of its relatively wimpy audio amp in the 1700-Auburn competition. The D-808 seems to throw in some extra noise in the 530-SeaTac reception, although the signal quality didn't seem to be improved with the higher noise level. Someone could say that that the CC Skywave had superior reception of 530-SeaTac, simply because of the lower level of background noise. In any case, since the weak-signal reception capability of the two models seems to be roughly similar (except when the Skywave's wimpy audio amp throws in the towel), the overall verdict must be that the new D-808 is the value winner in the "supercharged" SSB travel DXing portable class. For the 1% of the MW-DXing community that still has the interest and capability to modify portables in this way, I would strongly suggest that you devote 
 your resourc
> >Â Â Â Â Â es to the new XHDATA D-808. Besides the much lower price, superior FM reception and powerful audio amp, it also provides decent Longwave performance (after you transplant the 7.5" MW loopstick into the model, that is). The next wacky operation scheduled here is a 7.5" Longwave loopstick transplant into the D-808-- which quite possibly could nail down a reputation as the best SSB-enhanced NDB-DXing travel portable on the planet.
> > 
> > 
> >Â Â Â Â 73 and Good DX,
> > 
> >Â Â Â Â Gary DeBock (in Puyallup, WA, USA)Â 
> >Â Â Â Â _______________________________________________
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