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Hi guy's long time listener first time caller,
I wrapped up my Metro Themed JTM45 Build today and am having a problem. All of my voltages check out but when I plug a guitar in I get absolutely nothing no guitar output. All my voltages check out within reason with the voltage chart included in the MetroAmp JTM45 instructions. I have double and triple checked my wiring, I even lifted the PTP board out to check my under board connections. Through my numerous look through's I have only caught one mistake on my end (0.10uf mustard cap was hooked to pin 1&3 rather than 2&3 now fixed of course).
I made a video to better help illustrate my problem (I just uploaded it to YouTube so it might take a little for them to process it)
The video is somewhat out of sync (Droid X2 is a horrible smartphone btw) but it helps illustrate what I try to explain below
But the main things I wanted to illustrate is:
* When nothing plugged in the amp behaves as you would expect (very quiet but still the normal hiss when volume is rolled up ect)
* When I was taking voltages of the amp it behaved as you would expect slight popping when probing for voltages as well as tapping V1 you can hear the slight normal microphonic)
* When a guitar is plugged in this is when it gets interesting, the amp becomes noisy with absolutely no guitar output. (The guitar as well as cables are in working order tested on my 100w MetroAmp Plexi.) The noise can be controlled using the tone stack knobs touching the bare metal knobs can take away some of the nose. Rotating the knobs can generate a weird space like alien noise making the knobs even more sensitive, even coming close to the knobs will cause the amp to change noise.
* Also could a bad mustard cap be responsible for these sorts of problems? I bought these from a eBay member in Greece, I have no idea how to test them ect.
I'm open to any and all suggestions
Here is my star grounding scheme from MetroAmp
Here is my voltage chart
Wall Voltage is 119.4 AC
Youtube Link
JTM45 Problem - YouTube
Thanks guys
I wrapped up my Metro Themed JTM45 Build today and am having a problem. All of my voltages check out but when I plug a guitar in I get absolutely nothing no guitar output. All my voltages check out within reason with the voltage chart included in the MetroAmp JTM45 instructions. I have double and triple checked my wiring, I even lifted the PTP board out to check my under board connections. Through my numerous look through's I have only caught one mistake on my end (0.10uf mustard cap was hooked to pin 1&3 rather than 2&3 now fixed of course).
I made a video to better help illustrate my problem (I just uploaded it to YouTube so it might take a little for them to process it)
The video is somewhat out of sync (Droid X2 is a horrible smartphone btw) but it helps illustrate what I try to explain below
But the main things I wanted to illustrate is:
* When nothing plugged in the amp behaves as you would expect (very quiet but still the normal hiss when volume is rolled up ect)
* When I was taking voltages of the amp it behaved as you would expect slight popping when probing for voltages as well as tapping V1 you can hear the slight normal microphonic)
* When a guitar is plugged in this is when it gets interesting, the amp becomes noisy with absolutely no guitar output. (The guitar as well as cables are in working order tested on my 100w MetroAmp Plexi.) The noise can be controlled using the tone stack knobs touching the bare metal knobs can take away some of the nose. Rotating the knobs can generate a weird space like alien noise making the knobs even more sensitive, even coming close to the knobs will cause the amp to change noise.
* Also could a bad mustard cap be responsible for these sorts of problems? I bought these from a eBay member in Greece, I have no idea how to test them ect.
I'm open to any and all suggestions
Here is my star grounding scheme from MetroAmp
Here is my voltage chart
Wall Voltage is 119.4 AC
Youtube Link
JTM45 Problem - YouTube
Thanks guys
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