DESCRIPTION: This auction is for a retro AIWA HS-PX303. It's one of the best walkmans ever made, considered by most (and also by me) to be the best sounding walkman ever made by AIWA. It's made of metal, very solid, not like those bulky, plastic ones.

It includes very advanced features, like HX Amorphous head, Dolby C, bi-azimuth auto adjustment head and the best DSL system ever embedded in a walkman by AIWA. The "L" (low) position at "2" setting is truly unbeliveable, and can only be compared to the "DOL" system on the legendary Boodo Khan, but much more configurable.

It's very compact and stylish, and actually only a bit bigger that a cassette. The "AIWA" logo is embossed on the front.

It has the following features:

- HX Amorphous head
- Bi-azimuth head adjustment
- Dolby B and C Noise reduction 
- Parametric DSL 
- Full Logic Controls
- 2-way auto-reverse
- Music sensor 
- Remote control (not included)
- Slim and very compact, full-metal body
- Made in Japan
- Serial no.: Z907076443

It's a nice unit for collectors, very rare to find (it's the only one in eBay at this moment).

STATUS: FULL WORKING, as it has been recently serviced.
Cosmetically the unit is in good condition, with a few, but still noticeable, scratches and three small dents (beside the volume knob, beside the opening button and in one corner). Battery compartment is in good condition without signs of leaked acid at all. For details, see the photos.
The sound is superb, even with dolby C. all capacitors and the belt have been replaced for new ones. However, when playing it takes a few seconds to achieve the desired volume power.

NOTE: As almost every PX303, sometimes it looks like it gets a bit fool, because when pressing stop it can start FF or REW. It happens also in my other two serviced PX303.

Listed at eBay here:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330813318285

If it is not commiting the stop command correctly, then it is usually either that the ribbon cable linking the door to the main PCB is damaged or there is contamination / dry joint on the logic control circuit on the main PCB.

Yeah, my technician told me that. In other of my PX303 (I have a few) the problem was the remote switch, and until he has discovered and replaced it was also a bit fool.

The problem is that there are no replaceable parts for this

(but I can live with this issue as long as when you press play it plays flawlessly)

The cause for this phenomenon is the potentiometer that controls the logic clock. it needs to be lubricated or replaced. It usually happens in high humidity areas.  

                       Clock adjustment of the PX30/PX303/PX900

Interesting... I wonder if the same equivalent potentiometer (Labelled SFR3 OSC ADJ) on the PX10/101/20/700 is also the culprit for the erroneous control too on those models.

Yep, they are basically the same.

But I don't see any SFR on the board...ahh wait you're looking at the schematics right? yes... on the board its the same as the PX303.

It usually cause by the crack solder joints on the ribbon cable to door. The potentiometer can be clean using contact cleaner.

Hello there, if I am not mistaken, the HS-PX303 = HS-PX900, the latter one I have just purchased and should receive soon-ish.  It was claimed that the max. volume with cassette produces a low sound.  Could this be a cap problem?  Also, do any of you know where to find a manual, or if you know an on-line shop for a belt, and perhaps replacement caps?

Cheers!!

Low sound at max volume probably means dead capacitors indeed. Replacement ones can be purchased online with stores like Digikey or Mouser. Be sure to have a look at Plop's guide:

http://REPLACEMENT ERROR/topic...or-replacement-guide

About the belt, I can't advise you too much to contact DocP and have a deal:

http://REPLACEMENT ERROR/topic...uare-cut-andamp-flat

Keep us informed about your restoration!

Hello,

Thanks for guiding. I've contacted DocP and am hoping he will be able to sort me out a new belt.

I don't know if this would be too technical here, but looking at the manual (I just went and purchased one) I am wondering if I have met my match!  I see listed 74 capacitors!  Yikes!!   From what I have been reading, it seems to me that the usual problems are only with those that are packed with electrolyte, is this correct?  In that case, there are "only" 10 of these (if I counted right).  Would it be wise to just outright replace all, or, try just to get to those which would directly be responsible for the low volume? If I look to the wiring diagram, it would seem there are C19 and C20 inline to the headphone jack.  Would it make sense to start there?

Also, I am not sure how things are to be read regarding capacitance values/voltages. In the manual I see things like, "CAP,ELECT 470-2".  Does this read "capacitor(with electrolyte) 470 microFarad, 2 Volt"?

And finally, about capacitor voltage.  As I understand, from the above example, these 2V caps are impossible to find. So, would using 3V, or, 4V, with the same rating (i.e. 470 microFarad) be OK?  I have read this and that about this issue, but, as I understand, the 2V rating just means like a maximum voltage above which one might start to pop the cap.  It does not mean the thing is actually running at 2V, right?  So if I replace with a 4V (rather than 2V), it just means I have an extra layer of "voltage padding", by pushing the safety threshold to allow 4V before popping the cap.  Is it correct?  I suppose size comes into it, such that the 4V cap must fit where the 2V cap was, but otherwise, it is electronically sound way to do things, yes?

Cheers!!

Sweet, thanks for the photo. I assume the px303 will look exactly like the px900 on the inside, so that is handy.  I can't wait til mine arrives!

Cheers!!

Hello,

Does anyone know the dimensions of the belt for the Aiwa HS-PX900?  I find it is 0.75 mm thick, and can measure the diameter and length with 2 results.  Result 1) I simply try to make a nice circle shape and measure the inner diameter, and come up with ~57-58mm. 2) I slide the belt over 2 pins held apart in cardboard to get a length of ~88mm.

Does this sound right (I've no idea how much this thing has stretched by now)?  I should make the length, or, diameter smaller for a new, unstretched belt, but I am not sure how much to knock off the value?  Anyone with an idea?

Cheers!!