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No voltage on pins 8-19 on SX-1050 awr 103 board????!!!!

markthefixer said:
There is one other gotcha waiting, if ALL THREE speaker switches are turned on at the same time, NO SPEAKERS are connected. BUT the headphones stay live.......

QUOTE]

Another tidbit of information that makes this site so valuable. I never knew that you couldn't use all three speaker output buttons at once. I don't remember ever reading this in any operators manual. I checked this on my SX-1980 and it's the same way. Thank You Mark and Thanks to all the AK techs.
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Could also look for a used working replacement PS board on that famous auction site, might be a cost effective alternative . . .
 
markallen said:
Could also look for a used working replacement PS board on that famous auction site, might be a cost effective alternative . . .
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Better than six and a half bucks plus ($4 or $7) shipping??????? :scratch2:

For another 30 years of expected service life?
 
markthefixer said:
Better than six and a half bucks plus ($2 or $6) shipping??????? :scratch2:

For another 30 years of expected service life?
Click to expand...

Oops, didn't note the inventory had costs attached, not bad at all, possibly a bit more time involved? I defer to your experience, I still appreciate the fact that you had helped me resurrect the power supply on my SX-980, oh, about a year ago, still going strong, but apparently not nearly as involved as the problem this SX-1050 problem seems to have.
 
Mark the part# you supplied for transistor Q5 2SB507P did not match any #'s at mouser! you also transposed the lettersXlr for Xrl for the caps!
 
copied from a (my) mouser.com invoice:
512-KSA940TU_Q
copied from my post
512-ksa940otu_Q
copied from mouser catalog entry
512-KSA940TU_Q

for some reason it doesn't like the lower case or the _ using 512-ksa940 gets a bunch of entries, in which there is ONLY 1, the 512-KSA940TU_Q which allows quantities under 1000 .

The other part number in that order on mouser's site using the _Q suffix works
512-ksc2073tu_q

But the
140-XRL63V2.2-RC
xrl <> xlr screw up is my bad....
I DO try to watch out for that...

and:
If you wish to go with high temperature (105 c) capacitors, instead of general
capacitors (85 c) change the XRL in the part number to HTRL
makes more sense....


Did you know that the incredible SR-71 Blackbird recon aircraft was originally named the RS - 71 ??? and when President Lyndon B. Johnson misnamed it in a public appearance, they CHANGED the name (including ALL the drawings) in order not to embarass him???

So, sorry.... MY bad....
 
Hey with the remodeling and the forum I'm not suprised you would make an error or two now and then thanks for the info. watch them keys!
 
After you CLEAN the regulator board, and then rebuild it, before applying power a physical inspection of the unit is in order to find other goo to be removed from the liquid spillage, because as I read the thread, it seems the actual electronic carnage was created recently, as opposed to when the possible spill occurred.

If you find it hard to work on the board in place, I sometimes desolder the pins that the wires are wrapped on and remove them from the board after CAREFULLY MARKING EACH ONE'S POSITION. The wire wraps should not be disturbed, as they will NEVER go back again. Plus there is the danger of the wire breaking (NOT long enough, no less) off. If you desolder the pins, DON'T reconnect anything when you are done with the board, as the disconnected state can be an advantage in troubleshooting.

I also think before power is applied, a LOT of other tests are indicated to assess whether or not the power supply will be damaged AGAIN and correct those conditions.

In the meantime, you will want to aquaint yourself with the DMM diode test setting and how it is used to evaluate transistors for damage.

This post should also help pierce the fog after reading EchoWars's landmark testing post. It establishes a methodical reporting format that eliminates confusion. Just copy it in toto and edit in your results for each transistor.
 
Just got back to the house. I really like your helpful info about repairing the board. I had always planned to remove the board as I have wire tags and just find it easier to be able to manipulate the board out of unit, not to mention removing any possibility of getting solder in unwanted places.Your testing links weill come in handy as well. Once again I thank you.
 
Removing the board is a mistake. Manipulate it, cut wire ties and move wires, and do what you have to do, but do not start clipping wirewrapped wires so you can solder-blob them back in place. My apologies, but it's always the sign of a clueless tech.

'Course, the unit is yours and you can do as you wish, but I thought I tell you what goes through a professional's mind when he sees such a repair. FWIW, I've rebuilt the regulator on many 1050's and found cutting or unwrapping the wirewrap totally unnecessary.
 
EW Itook a look at the board and have decided that it may be possable to repair it without removing it from the wires. thanks
 
markthefixer said:
If you find it hard to work on the board in place, I sometimes desolder the pins that the wires are wrapped on and remove them from the board after CAREFULLY MARKING EACH ONE'S POSITION. The wire wraps should not be disturbed, as they will NEVER go back again. Plus there is the danger of the wire breaking (NOT long enough, no less) off. If you desolder the pins, DON'T reconnect anything when you are done with the board, as the disconnected state can be an advantage in troubleshooting.
Click to expand...

I guess I didn't make myself clear enough (since even EW missed it), NEVER EVER DISTURB the WIRE WRAPS.

I INTENDED to say: unsolder the joint between the PC board to the SQUARE PIN on the underside of the PC board!!!

It takes a little care to resolder the pin into the hole squarely, but there is plenty of real estate and copper foil to work with, and it's a lot easier to do just a FEW joints accurately in an awkward position. Of course I use hemostats ("locking tweezers") and have gotten adept at the removal and replacement of the posts. Just MAKE SURE ALL the solder has been removed (pc board and the bottom of the pin) and the hole is NOT BLOCKED before trying to reinsert the pin.

The pins are NOT staked in place, the only thing holding them in is the solder on the PC board. IF (SHUDDER) you solder to the upper part of the pin for any reason, you are INVITING problems with that lower joint!!
 
Once again thanks, parts are on order, I'm looking forward to having my 1050 back! I've checked the unit physicly and have not noticed any areas of goo! I intend to take this very slow and be extremely careful as I want this to be correct. When I get my 1050 back up I will check every function again as well as all voltagepoints in schematics. and any other tests you think may be appropriate. thanks again.
 
Hi again Y'all, parts have finally arrived an I am now about to check and diagram transistor pinouts of original vs replacement parts. I will probably start on repair by this weekend. Sounds like fun!
 
The 2sa628 transistors at Q6 & Q7 will be a bit tricky, because the service manual doesn't list the lead layout anywhere, neither does the reference information I could find.

Thus BEFORE removing them, it will be necessary to identify which other components are connected to each pad, and by examining the schematic, infer which lead is which hole in the board. IF we are lucky, the symbol will be silkscreened on the board and it will be legible.
 
Mark on checking my schematics it appears the lead diagram shows which leg goes where. my board also has all transistor positions silkscreened with the trans diagram, NPN, PNP.
 
So far I have replaced all the capacitors and most of the transistors and all of the diodes. tomorrow I will replace the rest of the transistors. It's a slow process but it is progressing. I can only work on this project after work and in between "honey dos'" Later!
 
Take your time, I'm not planning on going anywhere.... I'd rather see it slow and correct, than have more fixing to do.

Hey, it's my 3000th post... who'da thunk.....:scratch2:
 
In my order to Mouser I missed ordering a couple transistors, they should be here Fri. I'll be in touch. everything is going smooth so far.
 
Well everything has been soldered in and the power applied, I seem to have gone from bad to worse! not only have the voltages remained as originally reported but now the relay which was clicking has stopped clicking.
 
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