President Jackson (Silver) PB-042AB (1986/88)

[Stronty]

Afternoon gents.

Looking for a sanity check here and some experience of rectifying and issue I suspect is with the Channel Display Sub Board (PC-783BA) & actual LED Board (PC-960).

Missing consistently 1 segment on each number, 2 segments in total.

I have removed this sub board, what a hassle that was.

(PC-783BA)7 Pin flex cable - to main board - continuity good.
(PC-783BA) Violet wire - to main board - continuity good.
(PC-783BA) Black wire - to push button sub board (PB-044) - continuity good.
(PC-960)Red wire - to main board - continuity good.
(PC-960)Yellow wire - to push button sub board (PB-044) - continuity good.

I've checked the 14 resistors 13x 0.680K and 1x 333.0 which looks correct.

Full disclosure, I have never disassembled a channel rotary switch in regards to splitting the wafers and cleaning the copper strips inside. I have manged in almost 20 yrs on this forum never to venture into such territory. It scares the bejeezus! in me just thinking about it . So I'd like to eliminate everything before that scenario if possible. I know it might be the thing in the end but I'm really hoping not.

I've checked continuity where possible and all good, beeps where they should be etc. but gets confusing when turning the dial so to speak.

Sense check! what quick and dirty (Not harmful) way would there be to check for lit segments while the sub board is out? Applying a small voltage, small amps is that sound? any thoughts or experience?

Other than that its a nice radio, relatively untouched and not had R43, R41, R47 replaced or C-31 removed. Possibly could do with a recap but 1 thing at a time and nothing look so off to make that necessary... unless an out of spec cap on the main board could be causing the symptoms on the channel segments...

Some pics of the sub boards.

3c534344-c908-4a1a-b2fc-20ffcdfd1b85.jpg

099dcf8f-5bf2-4d7c-a96f-a8dc2bb7f32f.jpg

Reference -

Jackson WHLE.jpg

[Buick Mackane]

Its a job for paul CBforever. No doubt he'll be along soon

[lambrettadave]

I checked a black jacko and it has the 960 board for channel changer but I can see the led board for it lts number

[Stronty]

Thanks for having a look lambrettadave, appreciate you having a look. after some switch cleaning fluid sprayed down the shaft from the back and lots of turning and wiggling the same 2 segments never even come close to lit.

Conclusion is the led unit is gone as usually from what I've read and watched you'd get some sign of life if the wafers were dirty.

so now onto a replacement red 16 pin, 2 digit, 7 segment, common anode hunt. That's fun, some seem to have 18 pin and all seem to come with a decimal point on each digit 16 or 18 pin. Bugs me a little the decimal point, rather not have it.

Has anyone out there found any without the decimal point in that configuration. Seems the searches don't easily determine that.

[14CS06]

Hello

Here

Tandy Electronique
18 boulevard Laromiguière
12000 RODEZ
France



https://www.tandy-electronique.com/piec ... ident.html

@+
Claude

[Stronty]

For reference.

b4dfbe9d-7087-4575-8d87-e8cd61d85d96.jpg

3276c072-7c72-4b9c-a4d5-111955ded262.jpg

Part Number on LED UR-202-63DL

[Stronty]

Afternoon Claude, thanks for the link. Tandy... wow long time since i saw that name. That was Radio Shack's outlet in the UK. Think they used the name when they bought a sewing machine business called Tandy but then it time was a direct replacement for Radio Shack here in the UK.

The one you link to does seem to have the decimal though and the price without postage considered is quite something :-).

Merci though and will keep it in mind.

[14CS06]

Hello

here from cb4ever104



https://www.ebay.ca/itm/134753362908?it ... SwMCVlG9fX

https://www.ebay.ca/sch/i.html?item=134 ... cb4ever104

@+
Claude

[Stronty]

Hey Claude, Yeah, i had looked for Paul's but nothing came up, that's down to my e-bay settings not showing international sellers. But as usual i found what i was looking for, fast airline from China , i had a couple of other things i needed anyway. Will update thread when things arrive and i get a chance to continue the replacement. Also got the resistors to carry out the AGC mod. if that all goes well i may well do the caps.

[cb4ever104]

Sorry for being late ! I have the leds listed on my uk eBay account Dougie, so you shouldn't have any issue finding them. Anyway. Looks like you've got one now. They're easy enough to test connected with a 9V battery. To be honest you've done most of the hard work already, so why don't you try and get over your channelselectorobia , and open the thing up and clean it I just did another one yesterday. The 1st time is always the worst. 30min job now for me.

Desolder the 20 pins , snd remove the selector. Carefully cut the 4 white tabs off. Keep them if you want. Remove the back plate , taking photos all the time. Then carefully remove the discs (they're numbered) and the green bits. The discs are tight on the shaft. Ease them out gently wiggling them from side to side and use your tails to get them out. They can go in 2 ways or backwards, so make sure to keep taking lots of images. Lay each piece on a table in the order that you removed them. Once you've removed all the bits , then clean each disc with alcohol, and use a blade to carefully scrape the ends of the metal prongs. I use a small screwdriver behind each one to support it while scraping. The screwdriver can also be used to bend them outwards slightly as they're spring loaded. Reassemble it , and either melt the original tabs back on . Stick a soldering iron in the hole to get some plastic to come out , or put a dab of epoxy on them (preferred). The key to all this is to take your time, and take a hundred photos, and write down the disc numbers in case you can't see them in the photos. A lot of the older Uniden radios will thank you once you've finished. Spraying cleaning fluid down them won't do much , as it won't get padt the 1st disc , and that one is a pll program pin one I think. Good luck!

[Stronty]

Thanks Paul, I found them but i was already down the Ali Express road and bought some bits a bobs while there.

if i have to, i will but the mechanism itself isn't stiff or sticky and my concern was it was the wafers but i did the 9v battery trick and an no point did i get a flicker of anything out of those 2 same segments, not a jot. therefore conclusion is they are in fact dead. If i have to, I'll take heed on your walk through though, methodical, traceable and no which way round should that go moment's.

See you when the parts arrive.

[14CS06]

Hello

For exemple

@+
Claude

[cb4ever104]

Merci Claude ! Yeah. Looks like the led is knackered then Dougie. Just for future info. You can actually get the led and channel selector out without removing the whole assembly. All you have to do is desolder any wires (ch9 , power etc) if they're in the way , and then bend the selector back on itself with the ribbon cable still connected and that'll give you access to either remove the led , or selector.

And BTW. The dots on the LEDs do not light up. They're not actually connected to anything on the ones I have. They do help in showing which way up it needs to be fitted. Be careful with that. I've soldered one in upside down before, although I haven't done it since , as I triple check it now

S

[Stronty]

Excellent info as always @Claude and @Paul. Watched a vid and allegedly there is a non square on one of the edges, its subtly more rounded than the other 3 on the LED unit which helps identify orientation. I can feel it on the original, it ever so slightly rounded. no idea if the same will be true of modern ones. yeah the decimal point will help with orientation and the print on the board has 1 rounded edge also.

My soldering has got better so not phased with removing stuff to get at things better and working in tight spaces is a pain, if the ribbon becomes a pain I'll just stick a new one in, got some spare I can cut if needs be.

[cb4ever104]

Even with leds with no dots. Pins 4 and 5 are the common anode/cathode connections , so you can check the led with a multimeter before you fit it. The segments will light up a bit when tested. Once you identify those 2 pins , then they're physically on the bottom side of the led , so you can also work out the correct orientation from that.