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XHDATA D-808 AM/FM/SW/SSB/Airband Portable Radio

Although it has been available for a while now, the more I heard about this radio the more intrigued I became. It seemed to be a radio I should get to know, partly due to its provenance, partly due to several positive field reports of its overall performance especially on AM and partly due to its reasonable price. I paid $112.87 + $10 Shipping from Harelan ecommerce on eBay although it costs less in areas other than the US. My radio arrived 34 days after I bought it which was within the promised time range given in the auction. Why so long? That’s where the history of the XHDATA D-808 gets interesting and it has to do with a lack of patent protection among Chinese manufacturers.

Redsun, who worked with C. Crane in designing their one-of-a-kind CC Skywave and Skywave SSB models, has no control over other manufacturers who are seemingly free to copy parts of those designs, and to modify them any way they want to. This is also the reason that manufacturers no longer provide schematics and service manuals for their products which used to be standard practice which is a sad state of affairs.

Such is the origin of the D-808. Evidently, to head-off conflicts with C. Crane, Redsun agreed not to export the XHDATA D-808 to the US, but eventually an enterprising eBay seller found a way to ship the radio to the US via Israel. Thus, the higher price than we would otherwise have had to pay (although I think the D-808 is still a bargain) and the longer shipping time frame as well. Normally I would hesitate to pay a premium for a radio not normally sold here but in the case of the D-808, reports of its performance indicated that it may be worth it.

Although the XHDATA D-808 is styled differently than the Skywave and is a bit larger, it is based on the same Silicon labs Si4735 DSP Chip, which is used in many radios including the popular C. Crane Skywave SSB, Eton Satellit and Traveler III. And while the D-808 eliminates the NOAA Weather Band of the Skywave radios (since that is a US-service it would make no sense in a radio not intended for the US market), there were a few enhancements which elevate the D-808’s performance up a notch – RDS on FM along with better sound quality and slightly better AM sensitivity. The primary reason for the superior AM is the D-808’s 3 7/8” ferrite rod antenna versus the 2 ¾” ferrite in the Skywave radios…this larger ferrite rod easily accounts for the difference I hear.

Features and Specifications:

FM: 87.5–108 MHz/64-108 MHz With FM RDS Stereo/Mono Switchable .1/.01 MHz Tuning Steps

MW: 520-1710 KHz/520-1620 KHz 10K/9K/1K Steps

LW: 150 – 450 KHz 9K/1K Steps

SW: 1711 – 29999 KHz 5K/1K Steps

Air: 118-137 MHz .25/.001 MHz Steps

SSB With Fine Tuning Control (Fine Tuning works on all bands)

Tune via Knob or Up/Down Buttons with ATS

Volume Thumbwheel

Direct Frequency Entry

Lock Mode

Clock/Alarm/Sleep Timer

MW/SW Bandwidths: 7) 6K, 4K, 3K, 2.5K, 2K, 1.8K and 1K

SSB Bandwidths: 6) 4K, 3K, 2.2K, 1.2K, 1K and 500 Hz

500 Memories

Switchable Display: Time (Default), Signal Strength/Signal To Noise ratio, Temp (Fahrenheit or Centigrade) and Alarm Time.

Illumination Can Be Automatic or locked on

Squelch Control (Works On all bands which is unusual)

Earphone Jack 3.5mm

Ext Antenna Jack 3.5mm for SW/FM/Air

Fast/Slow/Stop (Lock) Tuning Speeds

You can also defeat the Beep Tone by depressing the #5 Beep button with the radio off.

Light Button turns on the dial illumination permanently…a nice feature.

Reset Button

Power Source: USB rechargeable 18650 Li-ion 3.7v battery

Micro USB Cable and Carry Case Supplied

It is interesting to note that although many radios use the same Silicon labs Si4735 series DSP Chips, these chips offer many features which may not all be available in any one radio, as well as many settings the manufacturer can adjust to customize many details of operation. Add to this the fact that every radio will have its own ferrite rod AM antenna, SW/FM/Air whip antenna and speaker which will affect reception and sound quality and you can see that two radios can use the same DSP chip and yet be quite different in many ways. There are also, of course, many areas where performance will be identical…my own experience suggests that SW/FM/Air reception tends to be similar when the whip antennas are similar while AM reception will be different depending on the size of the built-in ferrite rod AM antenna.

Performance:

Grundig Satellit – C. Crane Skywave SSB – Tecsun PL-660 Bottom: XHDATA D-808

The XHDATA D-808’s AM performance ranks ** ½ in the AM Mega Shootout list which places it at the top for this size class of radio. On AM it outperforms well-known, larger radios like the Tecsun PL-660/680/880, Sony ICF-7600G/GR or even the much more deluxe Sangean ATS-909X using built in antennas, hearing faint signals which are nothing but hiss on those sets. The only medium to small size radios that match is AM sensitivity are the slightly larger Eton Satellit, the original Degen DE-1103 (not the later DSP version) and the discontinued Eton/Grundig E5/G5 twins. For its size it is one hot little AM radio.

FM Performance is also as good as it gets in the best of today’s DSP portables…it earns a solid ***** in the FM Mega Shootout list and offers selectable Stereo/Mono and RDS for FM which are welcome features. Contrary to what the manual says the antenna jack does work on FM although it does not disconnect the whip antenna. I simply collapsed the whip and tried it with a typical folded dipole and was able to improve several very weak stations. The Signal Metering was a decided help here with comparative numerical readouts of both signal strength and signal to noise ratio.

Shortwave too is excellent in this category. Comparing it with well-known models from Eton, Sangean, Sony and Tecsun it was very close over most of the SW spectrum compared with the hottest of current day SW portables. Again, this is not surprising as many of these radios use the same or similar DSP chips which seem to do wonders with the shorter whips you usually find on smaller radios. Occasionally the D-808 was just slightly less sensitive on very weak trace signals, but on other signals it ran with the best.  One radio here, the PL-660 does have the benefit of synchronous detection which works well and sometimes is a huge benefit. Notably, with all of these smallish radios including the larger ones such as the PL-660 and ATS-909X , holding the radio in your hand sometimes provides a large boost due to the counterpoise effect and moving any of the radios a few inches here or there often caused bigger differences in reception than the inherent differences in the radios. Also, it’s important to remember that far bigger sensitivity differences can be obtained with a short wire antenna, such as the common reel-up types.

SSB performance was good by portable standards. It was fairly easy to get natural voice quality and the continuous fine-tuning control with its numerical +/- readout is a joy. The Fine-Tuning knob works on all bands by the way.

I checked the antenna jack and found it was effective on SW, FM and Air bands. I had read some online comments that it worked on AM as well but mine does not. It’s possible this has been a running production change but it’s also possible one could plug in an external antenna and via inductive coupling or grounding get some increase in AM signals…I have observed this effect on many radios.

The XHDATA D-808 bandwidth filters seem to have excellent characteristics – AM/SW selectivity seems very good while maintaining good high frequency response at all but the very narrowest settings which allow great selectivity and sensitivity for signals at the threshold of audibility. FM selectivity is excellent and on par with the best of today’s DSP FM portables.

I also found that the Squelch control actually works in ALL bands which is an unusual feature – the manual states that it only works in Air band which is usually the case.

The XHDATA D-808 has a nice display which can show Time & Frequency together which is very convenient, along with additional options of Signal Strength/Signal to Noise Ratio, Temp (Fahrenheit or Centigrade), Alarm Set Time and Time which the radio defaults to when turned on. The signal readings are relative and can’t be directly related to typical S-Meter readings but nevertheless they provide interesting info about what you’re tuned to and can be a definite advantage while tuning or antenna aiming. Display Illumination is automatic or the Light Button will turn it on permanently if desired…another nice feature.

You can defeat the Beep Tone by depressing the #5 Beep button with the radio off.

Tuning is very flexible. You can use the Up/Down buttons which also offer Scanning and ATS functions, the Tuning Knob can be pressed in to toggle among Fast/Slow/Stop tuning speeds, and when left in Fast mode the Fine Tuning thumb wheel tunes in Slow Mode so you have instant access to two speed tuning without changing tuning modes. You can also directly enter a frequency which requires hitting the Freg key first. There are also 500 Memories set up in Pages for easy organization.

Sound quality is also very good for this size radio and in fact it falls right between the smaller Skywave/Skywave SSB and the larger radios such as the Eton, Sangean and Tecsuns we’ve mentioned.  The XHDATA is too large to be considered an Ultralight, but for its slightly larger size you do get slightly better sound.

Also on the plus side the D-808 seems to have no soft muting which makes it user friendly and great for just tuning around. Some have complained about the muting or chuffing while tuning but what I found is that both of these are greatly reduced in Slow Tuning mode. In that mode the volume does drop a bit while you tune but not so much that you can’t hear what you’re tuning through, and it releases quickly. Yes it could be better but it’s not bad.

Battery Life with the supplied 18650 Li-ion 3.7v battery is stated at 34 hours at normal volume even with the dial illumination on some of the time and my radio easily met that figure giving days of use between charges. At first, I thought I might have a bad battery because after I fully charged it and started to use the radio the battery strength indication dropped by one segment very quickly, but I found that this is just the way the meter behaves. The radio played on for several days of general use while the meter dropped slowly.

Lots Of Side By Side Comparisons

Of course, there have to be some weaknesses as well but given the small size of the D-808 I didn’t find many. The biggest omission is that there is no Local/DX switch or control to limit strong signals from external antennas and indeed, in some of my external antenna tests there was some overload which the larger portables could handle better. On the other hand, the Skywave has no external antenna jack or Local/Distant Switch. These features are common on all of the larger radios which I think speaks to the reality that as radios get smaller they are more geared to portability rather than to permanent installations tethered to external antennas, so there are better choices if you will often use an external antenna.

Some Notes Concerning the XHDATA D-808 Owner’s Manual:

It’s not the best manual but it will get you through most of what you need to learn. I found a few errors but there may be more. Some of these seem to be caused by the fact that the same DSP chip is usually programmed a bit differently in other radios.

*Although called out in the manual there is no “Charge Button” on the radio. The D-808  is designed to be always in automatic charging mode since it contains a rechargeable Li-ion battery.

* Squelch works on all bands contrary what the manual says.

* External Antenna Jack also works on FM but does not disconnect the whip antenna.

* Under “Time Set” the words “Time Set Key” are missing from the procedure.

Conclusion: The XHDATA D-808 certainly reflects the state of Chinese manufacturing today in both good and bad ways.

The Good is that innovation never stops. Even within a given model there are often (maybe I should say there are Usually) design changes along the way, such that a radio bought today may be internally revised from that same model bought only months before. This can represent a step forward or backward depending on the reasons for the revisions. But without a doubt they are churning out new models constantly and the overall state-of-the-art is in some ways better today than just a few years ago. The XHDATA D-808 is a perfect case in point…it seems it would not exist if C. Crane and Redsun had not worked to design the Skywave radios. It also represents an excellent deployment of the Silicon labs Si4735 DSP Chip, with great basic DSP performance unhampered by soft muting or questionable noise reduction programming, and with a great feature set.

The Bad is that there is seemingly no longer any protection of intellectual property. If any design can be taken, copied (they call it “reverse engineering”) and modified, that certainly might stifle development because it’s cheaper to copy an existing circuit than to design your own. I think it would be frustrating to sweat out and spend money on a new design only to find someone else had taken your radio and used it as a starting point for a new model.

With all that said I don’t usually get into the politics of things…I just wanted to explain how this radio came about and in what ways it is like and unlike the C. Crane Skywave radios. But for me, in the end, it’s all about the final product and I rate the XHDATA D-808 as a top performer in its category. It’s just a little larger than an Ultralight but smaller than what we typically call a paperback book or travel sized radio, and it may just become my new travel radio of choice.

Recommended!

Jay Allen

 

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