To clarify issues related to the Phenolic Board further, I examined the underside of the board.
There are numerous connections on the underside of this board as follows:
Solder lug 1 connects to solder lug 17
Solder lug 15 connects to solder lug 20
Solder lug 19 connects to solder lug 9
Solder lug 9 connects to solder lug11
Solder lug 12 connects to solder lug 13
Solder lug 26 has a light blue wire that connects to a lug on Black Relay K2
Solder lug 8 has a red wire that connects to a terminal on K3 and a terminal on K1.
Some of those jumper wires have black Cambric sleeving on them while some are bare wires. Obviously it is important to watch lead dress very carefully when reinstalling and securing the Phenolic Board to the chassis. It would be very easy to short out or pinch either the red wire or the light blue wire to the board or the chassis. Also, C8 being underneath the board, has to be carefully positioned so that it does not interfere with other parts such as the relays under it. The new parts used to replace existing electrolytics should be chosen smaller physically if at all possible to free up space and make assembly less critical.
Cambric sleeving is pretty tough, but if replacing items such as C8 the 250uF@35VDC electrolytic It may be wise to use Teflon sleeving on its leads.
I have made additional notes on my hand sketch of the chassis related to the physical components such as the volume control & motor assembly, the relays, power transformer, bridge rectifier and some related terminal strips and connectors. I will be working on an illustration of these parts showing some of the interconnecting wiring for a future post. Everything is so compact and packed that tracing wires and parts is quite a task. Anyone who tackles one of these needs to be really on guard to make sure they are tracing the correct wires to various parts. Some wires are the same color and only differ by the wire gauge used to connect certain parts.
I have mentioned that there are two flat washers that go between the Phenolic Board and the chassis mounting tabs under the board. Today while handling the unit a third flat washer fell out of the chassis and so far I have been unable to locate a spot where it may have come from. It has no marks on it to indicate that it was ever used in fastening any other parts such as a screw or terminal strip ground lug. I am beginning to suspect that it may have fallen loose into the chassis at the factory and has been lying inside ever since.
K3 and K1 are small white relays very similar to what Fisher used in their 500-C and 800-C receivers. K2, the reverse relay, is larger and has a thin black plastic cover over the top of it. The relays are arranged in this order: K3 (Volume) is close to the volume control motor, K1 (Tuning) is just behind K3 and K2 (Reverse) is behind K3.
I first thought that the center relay was K3, but instead it is K1 used for activating the tune feature. I need to check to see if K1 is still activating as soon as power is turned on. If it is not, perhaps the extra flat washer that fell out was causing that relay to turn on.
Joe