The Amp Garage

The tube is biased with a 1k resistor and a 22uF bypass cap. Additionally I added the 56V Zener protection as shown in the Fender Reverb Service Manual. Unfortunately I took no image of the wave form from the scope. The sine wave was not flattened on the top or bottom. However, I plan to build a sta...

Recently build a tube reverb based on a Guyatone Fr3000 schematic I found in the www. Driving the reverb tank is pretty similar to the Fender Reverb. The second half of the ECC83 is used as a buffer (cathode follower) at the of the chain. Additionally there are 3 JFET for dry signal, mix and volume....

I do not like to raise another discussion about standby switches and if they are useful or not, but I like to understand the advantages and disadvantages of different kind of implementations. Most Dumble schematics with an SS show them between first filter caps and choke. Due to Merlins guidelines t...

I didn't try measuring across the bias test jacks yet but I will definitely do on my next build. I am not so worried about the difference to 1 Ohm. My goal is to see same value on all 4 test jacks even if they are not exactly 1 Ohm. At the moment I have slightly more than 1A in the meter so I need t...

I like to double check and select my 1 Ohm resistors for bias adjustment. Unfortunately even expensive Multimeter are not able to accurately measure small resistors. So I ended up to build a measurement device for small resistors. Idea is to use a adjustable voltage regulator LM317 I usually use for...

I have a couple of these inductors in brand new condition. So if somebody need them and is located in Europe, give me a message