Sangean ATS-909X observations

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nanZor

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There are so many reviews out that I won't go over every functional detail. Here are some other observations on my Sangean ATS-909X running an early ver 1.18 firmware:

Yep, great audio and fit and finish are superb. Minor quibble with smooth volume knob and detented fast/slow tuning. When hand-holding it, I use a technique with my thumb laying flat across the knob like being the connecting rod to the wheels of a steam-engine. :) With the radio laying on it's stand, a two-fingered twisted fork is used. After a day of using it, I adapted to it ok.

No sync. Yawn - I can do without so no major loss to me.

Stainless steel whip as opposed to the usual chromed pot-metal. Nice.

You can take the audio down to very low levels without an abrupt cut-off or hearing any amplifier hiss. The jacks on the radio seem to be of a higher level than the usual junk out there. The audio itself is very nice, although I would like a deeper high-end roll-off when listening to ssb/cw.

Wall wart is clean! That is, my unit is an AC-to-AC adapter, and seems to be a glorified stepdown transformer, rather than trying to rectify and regulate a DC input. That regulation and rectification seems to happen inside the radio, where it seems well filtered and not pushing a bunch of rf back into the line. Seems like any noise you hear will be coming from your ac line, and nothing is added from the adapter itself.

On shortwave, using only the whip and running just from batteries, it seems like it loses sensitivity to the tune of approx 10db or so. What is missing under these conditions is the other half of the antenna, the ground. There isn't a handy ground screw to run a short wire across the ground with. That's ok, since I don't dx with portables and the supplied whip. I guess if you really need the ground, use the adapter or use an external antenna. OH, and make SURE that you have the rf-gain set to max.

External antenna input impedance is low, but it isn't 50 ohms. Yet it is low enough to have no problems with the usual simple L-tuners, T-tuners etc. For instance, the included wire-reel antenna works ok when plugged into the external antenna input, but with a simple L-tuner like the MFJ-16010 tuner plugged in between, it works wonders about 10mhz and below. I thought it would be a high-impedance jack, but nice to see it is low. Would be better if I knew what the real impedance was, but I just ran a small RG-58 bnc jumper with a few adapters to mate between the 909x and the MFJ and all was well.

Strong-signal handling is very nice. Even SSB seems to stay stable with the 20-over-9 signals encountered. (using the same antenna on an amateur Yaesu radio) Yes, you can push it over the edge, but it is much more capable in this regard than my venerable modified Grundig 750.. more on that later.

UGH! Yes, there's a built-in charger for NIMH batteries. If you have the battery switch set for nimh/nicad it will charge whenever the radio is off. HEED THE WARNING - do not try to charge alkalines by mistake! And what if the switch gets flaky and tries to mistakenly charge alkalines? My inclination for safety would be to always run from rechargeables in this case if you regularly use the adapter.

I think most of us here DON'T recommend using your precious radio as a battery charger for good reason. Still, I tested it, and it seems to be a quick-charger to the tune of 500ma or so. I suppose it must use some sort of delta-v detection for the EOC signal. Took about 4.5 hours to charge my 2400ma Imedions. I'm testing the effectiveness of the charger by draining and measuring the batteries in a Maha analyzer right now at a C/20 rate, so we'll see how effective the "Sangean charger" is. It adds an appreciable amount of heat inside, especially with close-packed batteries.

I'd rather see that money spent elsewhere on improving the radio instead. Maybe exchange the charger stuff for sync. At least Sangean didn't waste resources on some junk rechargeables that ultimately end up in landfills and let US get the batteries we want. I'm not trying to bag on Sangean specifically - I think all manufacturers should drop built-in charges completely. Instead, throw us some Sanyo Eneloops and the mating charger seperately if you must. :)

Missed keys / wrong keys: The cpu seems to take a little while to perform keyboard operations, so when I have to repeat keys it usually meant that I was just going to fast for it, so slow down. Maybe this has improved with versions of firmware beyond 1.18. I sure wish the firmware was actually user-upgradable, or if Sangean would publish what the actual changes between versions are (I think it is up to 1.3x or so now). I'll keep holding my breath on that one. :)

I'm not a major AM/FM dxer, so all I can say is that they sound great for me, and I'll pull out the little Grundig AN-200 tunable loop for casual bcb dxing.

SQUELCH - works really well for those times that you need/want it. Thing is, Sangean forgot to include AIRBAND to go along with the nice squelch! Maybe next time.

Summary: Despite my rant about the charger, I'm very glad to own this radio. Small details mean a lot to me. What I really see is that this radio wants to be in a bigger box - as a competitor to the Grundig Satellit 750. Throw some big VFO knobs on it, continuously variable bass/treble, maybe tighten up the narrow bandwidth a bit, and you'd have some real competition - and I'd be Sangean's first customer. There's a big radio trying to get outside the 909x chassis!
 

nanZor

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Note: The charger does reasonably well. Measuring the total amount of capacity during a low-current discharge in a Maha 9000 analyzer, they showed up at about 2300 mah. So yes, the charger in the 909X does a good job - although I still don't recommend taking the risk.
 

E-Man

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Yes, thanks for taking the time for your review. I have a DX-398 (ats-909) that I have enjoyed for years. I look forward to uprgrading to the 909X.
 

nanZor

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If you like the 909, I'm sure you'll like the 909X.

By the way, I forgot to mention that the display is great - very easy to read even when backlit. The contrast seems to be optimized for when it is laying down on it's fold-out stand, yet you can still read it at most angles.

One thing the display doesn't show is the bandwidth selection, so that's something to doublecheck if you don't notice it immediately by ear. Since the bandwidth switch also doubles as the FM mono/stereo switch, that is something to check when changing between FM and AM. SSB defaults to the narrow bandwidth (unchangeable) no matter what position the bandwidth selector is in.

I've really come to appreciate the small things - they could have gotten away with a cheaper quality whip rather than going stainless. The charger, even though I am not a fan of charging in the unit for any radio I have, is a quick-charger rathat than the typical slow-charger. Testing has shown that it actually performs well, and it takes additional engineering to pull that off when it comes to determining the end of charge. Using an AC-AC adapter helps prevent the wall wart from becoming a noise source in it's own right. And the quality of the audio is superb for the small speaker it is driving - rather than just being downright loud, it seems to have a smooth/flat frequency response, rather than an over-enhanced bass or treble to compensate. If you listen for content, the audio is a real pleasure for what it is. And I really liked what I saw inside - clean wave soldering, nice board layout, high-temp electrolytic caps, etc. Even with the detents, (just use your thumb instead of index finger) the slow ssb tuning is the best of any portable I have ever used.

I can't put my finger on it, but it almost seems like it was engineered as a radio that one of the engineers themselves might enjoy using, rather than just tossing a plastic box to the public for endless beta feedback for the next model. Well done, Sangean! Looking forward to the next (hopefully bigger "portatop" model).
 
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marcus45

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ats-909x digital signal processing

Hey there, I couldn't find anywhere else to post this question. What does the DSP on the 909x do? Is it noise reduction, filtering or auto gain control? Or is it all of the above? Thank you.
 

nanZor

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I would like a definitive answer to this myself!

It is disconcerting at first to see what appears to be a wicked-fast agc especially on ssb working well. Being old-school, I'd still prefer a slow or user-adjustable setting - but it may not be necessary with DSP. But being a portable, I'm not losing too much sleep over it. :) It does seem to be more pleasant than my Tecsun 660, although i don't want to start a portable war over it.

Perhaps the Radiolabs guys can provide more info - I'm not sure if their filtering mods are actual swapouts of crystal filters, or just adjustments to the dsp itself.

What I can say is that the radio sounds nice and seems well-behaved, but some reviews that gush over the dsp capabilities may be a bit over the top - more marketing than engineering IMO. In no way does it even compare to a higher-end analog radio.
 

grogan

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I have a like new,olny a few months old. ATS 909 the newest before the X model and was thinking about selling for the right price.Great radio Just don't use it. Was going to buy the X version but HRO said for the extra cash it was not worth it. Box manual roll up antenna charger cary case etc. Might put it on Ebay.
 

nanZor

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The Radiolabs mod is interesting, although I've always wanted to know exactly what the modified filters are for - AM/FM/SSB etc? What are the shape factors? How is the extra sensitivity obtained and by what amount?

There are now two Yahoo groups for those interested - the original 909x and the Radiolabs mod'ed 909x btw.
 

nanZor

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You get what you pay for! In this case, the seemingly less sensitivity on the whip results in a more stable professional receiver, resistant to the typical overload / desense that most portables are prone to. Of course you have to look at the whole package to make sure it isn't just deaf because it is cheap.

The easiest way to increase the sensitivity, is to clamp on the included 30-foot wire-reel to the whip, and run it out for a few more feet at least. Quite frankly, the sensitivity on the 909x is what I consider "normal" and well-engineered, and many of today's portables are superficially too sensitive.

Super high rf-gain is an old over the counter marketing trick to see how many people get lured into thinking one receiver is better than the other merely by how much hiss can be heard in the store. :)
 
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jtcase

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ATS-909X Balun Mod

I had been evaluating this radio against the new Tecsun PL-880. I wound up returning the Tecsun for a refund, and kept the ATS-909X. I agree with everything Hertzian has said (wonderful review BTW), but wanted to add some comments on the sensitivity of the whip antenna on shortwave as this was my only area of concern with the radio.

One of the members on the Yahoo Group for the Sangean ATS-909X has come up with a simple BALUN modification for the whip antenna to cure an impedance mismatch. The mod involves making up a 4:1 BALUN using a simple ferrite core and some magnet wire and installing it between the whip antenna and the receiver. Instructions for the mod are excellently written up, with photos, and are available in the files section of the ATS-909X group. This mod yields a clear improvement in sensitivity, moving the S Meter an average of 3 bars and more.

This mod has completely transformed my radio on the whip antenna. Where before it had a hard time keeping up with the Tecsun PL-660 and PL-880, it now clearly surpasses both in sensitivity and ability to recover weak signals. This has quickly become my favorite radio, and I think it is the best radio in its price class. The Tecsun PL-880 has a lot going for it, but the miserable sync detector performance, and the weak signal SSB distortion problems will have to be addressed by Tecsun before I think it can be considered a good alternative to the ATS-909X. Whether the problems with SSB reception on the PL-880 are firmware related, or the result of a poorly designed AGC are still being discussed in that Yahoo Group but it does not appear a resolution will come anytime soon.
 

nanZor

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I just wish mine lasted a bit longer, despite the appearance of decent build quality.

Frankly, I've given up on this market segment of radios. Maybe I'm too picky, even though I started with a Heathkit SW-717. :)
 

jtcase

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I know what you are talking about, as I started out with an Allied Knight-kit Star Roamer back in 1965.

I'm having a lot of fun with the ATS-909X. I like it so much I decided to get a second unit, and will order the clearmod one from Radiolabs. My current model is white, so I think I will order the new one in black to be able to quickly tell them apart. It will be interesting to compare the 2.
 

SCPD

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I know what you are talking about, as I started out with an Allied Knight-kit Star Roamer back in 1965.

I'm having a lot of fun with the ATS-909X. I like it so much I decided to get a second unit, and will order the clearmod one from Radiolabs. My current model is white, so I think I will order the new one in black to be able to quickly tell them apart. It will be interesting to compare the 2.

Be careful about the black models...

http://forums.radioreference.com/hf-mw-lw-equipment/278443-do-not-buy-sangean-ats-909x.html
 

GB46

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Another observation about the ATS-909x

Sorry about replying to a very old thread, but I just thought I'd mention that the English manual for this receiver specifies the slow tuning step for SSB as 40 kHz, when it's actually 40 hz. Can you imagine turning the tuning dial just a speck and losing the station altogether by winding up 40 kHz up or down the band? :lol:

Actually, that kind of thing would have happened to me with some of the cheap SW radios I had as a kid back in the 50s and 60s.
 
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