Amplifone vector monitor - vertical collapse

As for upgrades, there aren't many parts that need to be upgraded to different values on Amp deflection boards. You do want to follow what is in the FAQ however, regarding replacing the 0-ohm jumpers with straight wires.
 
It looks like they have all been replaced. I think. As far as shotgun parts....it's more about getting everything I'm likely to need at once. I'm in like at Fry's right now with the diode. But most of what I want they don't have. And it's lower quality.
 
The diodes you can get anywhere. They're literally one of the most common parts in all of electronics, and any dead board probably has a few.

The other stuff is more specialized. You'll need to go to one of the online folks. But you should figure out what you really need first.
 
Now that Radio Shack is gone, where else can you pick up diodes typically. The only other place I know close by is Fry's Electronics and they inventory is terrible. I just bought the last one they have and they may not restock for ages.

I just replaced it by the way. I'll take capacitor readings again and post them shortly.
 
Ok I re-measured them all. The readings are exactly the same except on Q5. I put the new readings in parenthesis on that one.

Q4- PNP
B to E: Short
B to C: Short
E to B: Short
C to B: Short
C to E: Short

Q5- NPN
B to E: Drop (Open)
B to C: Short
E to B: Short (Drop)
C to B: Short
C to E: Drop (Open)

Q15- NPN
B to E: Open
B to C: Short
E to B: Drop
C to B: Short
C to E: Open

Q14- PNP
B to E: Drop
B to C: Short
E to B: Open
C to B: Short
C to E: Drop

Which still....to me....looks like all 4 of them are bad.... correct?
 
You're measuring them all in-circuit, right? Just confirming.

Have you checked any of the other smaller TO-92 package transistors below them?

It's odd that all four that you listed would be bad together. I'm not saying they aren't necessarily, but the next step would be to pull them and confirm, as you may get different readings when you do. However the fact that all four are bad (if they are) suggests something else at play, than just a standard deflection failure.

Did all four have the proper silpads and insulating washers? (Check to make sure they aren't shorted to the heatsink, before removing them).

You'll also want to keep checking back, through the other transistors and other components, working your way back to the power supply section. I wonder if a PS issue could have been the root cause, as it's really unlikely for both axes' transistors to fully fry on their own. Was the board

Also, regarding parts, I'm surprised if Fry's doesn't have 1N00x diodes, as they're super basic. I don't know if there are other local electronics places up your way, but when I am on the peninsula, San Mateo Electronics is a little hole in the wall place I'll go for basic stuff in a pinch. They're right off of El Camino. The transistors and other parts you're going to need will be too specialized for them, so you'll need to go online. Digikey usually gets me my orders in 48 hours, most of the time.

Also, you're likely going to need to sub those four transistors. I use the ZTX653/753's for all vector deflection boards. Different package though. If you want something closer to original, you're going to have to find a different source. Bill's page is pretty useful.

www.biltronix.com/transistor_subs_01.html

Also, you mentioned that you had a horizontal line on the display, which suggests one axis might have been working, which doesn't jibe with what you're seeing with the transistors, so there's something else suspicious there. You may want to doublecheck.

What function on what meter are you using to measure the transistors? Do you have a known-good transistor you can just sanity check the meter with?
 
You're measuring them all in-circuit, right? Just confirming.

Have you checked any of the other smaller TO-92 package transistors below them?

It's odd that all four that you listed would be bad together. I'm not saying they aren't necessarily, but the next step would be to pull them and confirm, as you may get different readings when you do. However the fact that all four are bad (if they are) suggests something else at play, than just a standard deflection failure.

Did all four have the proper silpads and insulating washers? (Check to make sure they aren't shorted to the heatsink, before removing them).

You'll also want to keep checking back, through the other transistors and other components, working your way back to the power supply section. I wonder if a PS issue could have been the root cause, as it's really unlikely for both axes' transistors to fully fry on their own. Was the board

Also, regarding parts, I'm surprised if Fry's doesn't have 1N00x diodes, as they're super basic. I don't know if there are other local electronics places up your way, but when I am on the peninsula, San Mateo Electronics is a little hole in the wall place I'll go for basic stuff in a pinch. They're right off of El Camino. The transistors and other parts you're going to need will be too specialized for them, so you'll need to go online. Digikey usually gets me my orders in 48 hours, most of the time.

Also, you're likely going to need to sub those four transistors. I use the ZTX653/753's for all vector deflection boards. Different package though. If you want something closer to original, you're going to have to find a different source. Bill's page is pretty useful.

www.biltronix.com/transistor_subs_01.html

Also, you mentioned that you had a horizontal line on the display, which suggests one axis might have been working, which doesn't jibe with what you're seeing with the transistors, so there's something else suspicious there. You may want to doublecheck.

What function on what meter are you using to measure the transistors? Do you have a known-good transistor you can just sanity check the meter with?

I partially checked all the other transistors. Meaning that I didn't go into the same detail but I did quick checks on a couple legs each and nothing seemed out of whack.

You are right about the horizontal line. But....I powered it up again before pulling the board and I was getting zero graphics at all. So whatever fried one axis at first may have fried the rest of it the next time I powered on.

All four had mica insulators and none were shorted to the heat sink. I checked that before removing the two that I already pulled.

And yes, I was checking them in-circuit. I can pull them and check that way. I feel like I would understand the readings better anyway. It's just a pain in the butt but no big deal.
 
I partially checked all the other transistors. Meaning that I didn't go into the same detail but I did quick checks on a couple legs each and nothing seemed out of whack.

You are right about the horizontal line. But....I powered it up again before pulling the board and I was getting zero graphics at all. So whatever fried one axis at first may have fried the rest of it the next time I powered on.

All four had mica insulators and none were shorted to the heat sink. I checked that before removing the two that I already pulled.

And yes, I was checking them in-circuit. I can pull them and check that way. I feel like I would understand the readings better anyway. It's just a pain in the butt but no big deal.


You definitely want to check all of the other small transistors on the board. Just make sure you get two drops in one direction, and opens in the opposite, though you may also get one drop and one open in the opposite, due to other nearby parts. So you want two drops in one direction, and at least one drop in the other, but definitely no shorts in any direction, for any combo of pins.

Regarding the silpads, I was referring to the four smaller transistors that are mounted to the heatsink. Those need small square silpads and the tiny insulating washers, to make sure the screws don't touch the heatsink. However if the game was working at one point, they're probably fine. However you just want to make sure not to lose them when you remove them (or the ferrite beads on the two outer transistors), which I can all see from your pics.
 
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