1984 Garrett AM-2 Schematics?

[homefire]

Yes, would like to compair to the S3!

[Melbeta]

Someone likely fooled with the unit.....

Found the info from a Findmall forum member who has the identical AM-2. But, without the IC's ID numbers being ground off. So I am good to go if they need to be replaced.

I obtained this AM-2 in a non working condition. Found several cracked resistors and a broken one. So just for the sake of it started to replace all the resistors and the 3 electro caps. The Disc and GB pot were also kind of griddy feeling, and a broken meter, those are being replaced also. Hopefully will once again work when finished.

If anyone is interested I will post a pict and the IC numbers

It is not common to find several cracked or broken resistors, those usually are broken by someone that does not know electronics. I found they would try to move parts slightly, to see if a problem went away. They would use a small knive blade or small screwdriver to pry and lift up the resistor and other parts, then move them around, here and there on the board, to see if the problem disappeareed, and then they broke or cracked the ceramic of the resistor when prying. Check the diodes too, some of them may be cracked.

Moving things around can cause a cold solder joint by cracks in the solder area. Can resolder all connections on the trace side. I do that first of all on all repairs.

Seen that a lot when guys fooled with things they did not know about. They would turn anything that was turnable. You may have some pots that are slightly turned also. But that is just an guess from me, based upon past experience from electronics that people entered and began to play around with the parts trying to fix them that way. They even put small metal hex allen wrenches into the powdered iron ferrite slugs in pots, and broke the inside tuning slugs. Only supposed to use plastic hex tuning tools in those to avoid breaking or cracking the soft ferrite tunning slugs...
Melbeta

[SVEN1]

#1 P8742/ CD4001BCN MM5601BN

#2 F4011BPC 8222

#3 CD4016BE RCA H 719

#4#5#6#7#8 ALL SAME M8730 AT LM 358N

[SVEN1]

DIODES

Just an added note as it's almost impossible to discern what diodes are used on the AM-2.
Did not get a response from Garrett. Managed to figure out the part numbers so I can replace them.

Diode with green band next to two electro caps near marking #7 is a N15233B
All other diodes are 1N914AF

[SVEN1]

Just an added note as it's almost impossible to discern what diodes are used on the AM-2.
Did not get a response from Garrett. Managed to figure out the part numbers so I can replace them.

Diode with green band next to two electro caps near marking #7 is a N15233B
All other diodes are 1N914AF

Finally got a response from Garrett and the 914 are the same as 1N4148

[kt315]

Diode with green band next to two electro caps near marking #7 is a N15233B

may be 1N5233B? then it's Zener 6.0V.

[SVEN1]

may be 1N5233B? then it's Zener 6.0V.

That's exactly what it is.
A packet of them arrived a couple days ago, so i can replace the one on the board.
Replacing all the 914's with the 4148 diodes, which I have have plenty of.