1979 Marshall JMP 2203 - Circuit Question

[JB3]

Hey all,

Long time reader over the years, first time registrant and poster. I recently acquired a '79 Marshall JMP 2203 and I was hoping that folks could help me in identifying whether this looks mostly stock or has had alteration over time. It has the original caps and iron in it, but I'm not certain other than that. Here are some pics. Thanks!

[gldtp99]

There is a snubber cap across one V1 100k plate load resistors----- whoever did the work also heat damaged the .022uF cap next to it with their soldering iron----- poor quality work-----also someone did the Cheap/Easy 6550-to-EL34 Bias Circuit Conversion by piggybacking a 1 watt resistor across the existing bias range resistor--- a better tech would have pulled the PCB and replaced the several resistors to do the proper 6550/EL34 bias circuit conversion---- and most likely replaced the bias e-caps when the board was pulled.

Gut pic of my stock '81 JMP 2204:

[JB3]

Perfect. Thank you! I also have a few shots of my other '79 which looks drastically different. I see a red and yellow "Lego" in there, but are those other 7 rounded yellow some form of mustards?