I'm new at reading O-Scopes but it looks like the the audio signal is being compressed? What's the modulation at?
Sorry I can't explain it better. I guess it is a form of compression, dynamic range compression. Maybe sometime soon I'll do a test showing a demodulated signal and how it relates to an audio signal at the circuit input. Thanks so much again for posting that project.
I am not a tech by any means, but if I remember correctly the SP-1A has an mic pre-amp circuit so it should go before the echo board. The echo board may also have a mic pre-amp also so you may need to watch that. 'Just applying the garage in garage out theory you want to make sure you have everything clean before applying echo effects. The Top Gun Tec website should have the install instructions.
Hold ON!
There is a numbering Error on the Schematic...
Original...
View attachment 40216
WHY?
Q1 and Q2 are not correctly
identified...
MK1 needs to be able to operate at
Voltage Range stated in Schematic...
REVISED
View attachment 40220
Radio Shack isn't around like they used to, so the Electret stated in the schematic isn't around either. So you'll have to take into consideration the Operational Voltage Range the Element is capable of operating in. R13 and R14 would have put too much emphasis (Working Voltages) on the higher end of many of the newer Condenser elements that would work, yet not in the Voltage Range the circuit biased the ORIGINAL part within.
(If I'm becoming a PITA - let me know...)
Andy, I'm lost my friend. I don't think that's the one I'm referring to.
This be the one
View attachment 40236