I have decided to rebuild my Model 16. In addition to a standard recap I also want to get as close to a 16B as possible. I compared the schematics and have found 9 differences. Most of them are just part swaps, three involve some rewiring. The transformers are different between the models I do not plan to make any changes there. So I likely won't get the power boost but am hoping for the sonic improvements. Below are my plans. Any input is appreciated.
I want to thank Chris for his awesome post on Faultline for his Model 32 rebuild. I would not be attempting this without that post.
Part swaps
I will also remount the outputs with some fresh insulators and compound.
I need to sit on this for a couple days to think through this some more. I hope to get my order in this weekend.
I want to thank Chris for his awesome post on Faultline for his Model 32 rebuild. I would not be attempting this without that post.
Part swaps
- Q1 - MPSA70 (considering NOS)
- C8 - .022uf 100V cap
- Q2 - MPSA20 (considering NOS)
- Q5 - MPSA20 (considering NOS)
- R35 - 2.2K 2W Resistor
- R39 - 750k .5W Resistor
- C22 - 10uf 64V cap (across R39 and R40)
- CR6 thru CR9 - Are replaced with an actual bridge rectifier. I plan to just replace the diode network with four UF4004. Originals were SR154 and SR154R. I can't find any info on the SR154R. The UF4004 seems to be good to replace the SR154 though. Any input here is appreciated.
- CR7 and CR8 are now 1N5393 and wired across the bridge rectifier
- Replace all resistors
- Replace bridge rectifier with KBPC602PBF (but my 16 is different than the 32 here so I won't be doing this)
- Replace Q13 & Q14 - BC546B (pinout is reversed)
- Replace Q12 - MJE182G (pinout is different)
- Replace all caps - I will use Elna Silmics here
- I will follow Chris and use Nichicon TVX. For the oddball 125uf, I will piggyback a 100uf and a 33uf.
- Considering Nichicon LKG for the filter caps. They are larger capacitance than I want (8200uf) but with it starting at 5000uf then the first service bulletin to 6800uf, then another to 6900uf, I don't want to go with the 6800uf.
- I can't find R44 referenced in 69-12/16-1. I'm guessing I am either blind or this was added after the schematics that I have.
I will also remount the outputs with some fresh insulators and compound.
I need to sit on this for a couple days to think through this some more. I hope to get my order in this weekend.