OK, so I'm building a second Pork Barrel by Mad Bean. 1st one is working well, so well I have an order build another for my Brother.
I got a lot of 3007/3101 ic's from seller on Ebay. One set is in my #1 PB Chorus and working well.
In my down time, I build an audio probe so I could be more efficient at resolving issue with my builds.
So I have the PCB populated except the 2 pots. I have inserted the pots without soldering to test the PCB. "Rock it before you box it"
I'm getting good voltages compared to the #1 PB pedal.
I'm getting sound from pin 3 of the BBD but nothing from pin 7 or 8 which is the output of the BBD.
I'm getting dry sound from the 4558 on pin 1 and 7 - the outputs - no chorus effect.
Should you hear the signal/sound on the BBD on pin 7 and 8?
Well I assume you socketed the chips in the first pedal, why not just switch the chips round?
Quote from: Scruffie on March 19, 2017, 09:43:36 PM
Well I assume you socketed the chips in the first pedal, why not just switch the chips round?
Yes, all IC's are socketed.
Well, I'm a cowardly lion. I was afraid of blowing the only working 3007 I had.
But... I did it anyway.
Results are:
1. From the signal probe you should hear signal from pin 7 & 8 on the BBD if the chip is working.
2. None of the 9 3007 I have worked in PB #1
3. 3007 #10 that works in PB #1 works in the PCB for PB #2 (confirming the new PCB is correct and functioning)
4. Contacted the seller on Ebay and they claim they will replace the 9 3007's. If so fine, if not lesson learned, spend the extra at Small Bear for a known working 3007 IC.
Thanks for your input
Welcome to the club of "Folks burned by Ebay 3007s". We need to make a merit badge for the group or something.
Even when they aren't selling fake chips, they're usually pulling stock taken from old karaoke machines and burn or zap the chips in the process. Very frustrating.... but the prices are so tempting.
To be fair, you were quite lucky, you beat 1 in 10 odds to put the only working chip in your first build! It's the little victories.
By the way... they'll probably send you more fake MN3007.
Quote from: Scruffie on March 19, 2017, 10:52:31 PM
To be fair, you were quite lucky, you beat 1 in 10 odds to put the only working chip in your first build! It's the little victories.
By the way... they'll probably send you more fake MN3007.
I would agree, may not be worth the postage to send them back! Put that money toward a known chip from Small Bear.