Hi klnglim!
I see you are still trying to sort out your amp. I can't be much help as I don't know exactly what you've done but I would go back to basics and double check a few things:
your traces new and old - your repairs to the board look excellent
your parts - are the specs the same. It is easy to misread some parts names, for example I mistook a .68R for a .68K resistor, also I used the wrong type of diode, both of which could have stopped the amp working. Are your parts all up to spec, the right way round etc.
wires all connected correctly.
I double and triple checked mine recently and still missed a few things!
All pretty basic but a mistake at this stage will be critical. It is difficult to know what's wrong when you have done so much.
When you've got the amp up and running you must complete all the upgrades to date, that way your amp will be pretty spectacular lol!
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Now I try other method, use good quality jumper cable as prototype style, there are a lot spaghetti wiring around, this project will finish soon.
All the resistors have changed to Dale & Mills, some electrolytic caps replaced with Nichicon audio grade, only power supply caps remain unchanged
Some Diodes have replaced with 5 Watts instead of 1 Watts, 2 rectifier changed to brand new 2W10 model
Mundolf EVO & EVO oil replace all WIMA caps, coupling and WCF
WIMA MKS2 replaced all the mini caps artound op-amp and gain switch
Overall Can be said 90% of components include gain switch, op-amp, potentiometer, fuses, Voltage regulator, MOSFET, NPN PNP transistors, headphone protector relay & 2 sets uA meter inside this tube amp is brand new
May be sound like I m a bit over spend all those parts, actual reason is I can get those parts replacement with very low price.
Because of those super cheap low cost parts, so why not replace all with brand new, right?
Beside new parts replacement, the ground shortage issue inside the PCB also had already been fixed.
The board have already been cleaned with Methal Spirit few times as well. The reason I seldom use ISO Alcohol is the board felt a bit sticky after dry and uncomfort with finger touch.
Hopefully, If this amp is successful to turn on, of course I will post to share.
If still no luck cant turn it on, then I'll have to work and study harder again until successful result show
Have to learn from Edison spirit : There are no failure in entire life but only to learn and find the best way to work it out! That means never give up! LOL
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