Harmonic Percolator- Tagboard.. switch wiring?

[megatrav]

Update time!
I put in a new 2N34A and a new 2N3565. I also swapped those large caps for smaller ones.
Good news is it makes sound.. sort of. I am able to hear the guitar coming through but there is a crazy amount of feedback and oscillation. When I flip the switch it just oscillates. No distinguishable notes from the guitar come through. I made sure my pin out was right on the 2N34A and I even tried swapping the 2N3565 and it did the same thing with it in either way.
Could my 2N34A be in the wrong way?

 

[megatrav]

I know that I need to check my voltages. I will report back once I have done so.
The 2N3565 pin out isn't obvious since it is the older style. It's fully round on the top

 

[megatrav]

Okay so unless I am not sure if I am testing these correctly. I am taking the ground from the multimeter and touching a ground point and then using the hot to go between the different legs.
These are the results I got-
2N34a
B: .867
C: .8
E: .81

2N3565
E: .87
B: 1.4
C: 5.67

I am not sure what this means, other than those numbers do not match the ones in the chart.
I have double checked all of my resistors and capacitors to make sure they are the right value and in the right spot.

Not sure what's going wrong

 

[megatrav]

I am genuinely stumped. I spent last night and some of this morning verifying the board and the wires to make sure everything is going to the right place.

 

[megatrav]

@Mcknib @fig any thoughts?

 

[fig]

What value resistor is between BC of the transistor? It calls for a 750kΩ

Edit: Sorry, the 3565

 

[megatrav]

What value resistor is between BC of the transistor? It calls for a 750kΩ

Edit: Sorry, the 3565

Looks like I might have stuck a 680k in there. I will swap it for a 750k

 

[megatrav]

If that works, I am going to change my name on here to "Biggest dumb dumb on earth"

 

[Feral Feline]

Careful what you wish for, Megatrav.

Besides, I'm not giving up my title that easily...

 

[Bricksnbeatles]

Where are you all getting your tag board? I rarely use it (only for BS vintagey looking stuff), but I always used to get it on eBay and the seller I used to buy from disappeared— can’t find anyone else on eBay who doesn’t charge an arm and a leg for shipping to the US

 

[megatrav]

Where are you all getting your tag board? I rarely use it (only for BS vintagey looking stuff), but I always used to get it on eBay and the seller I used to buy from disappeared— can’t find anyone else on eBay who doesn’t charge an arm and a leg for shipping to the US

https://www.hificollective.co.uk/search/site?text=tag board

This is where I ordered mine

 

[Feral Feline]

Local shop and Amplified Parts is where I got mine.

 

[Mcknib]

Is that rust on top of your 2N404?

Your transistors aren't biasing correctly looking at your voltages, did you try tepee'ing a 67K to the 680K as I said I don't know what effect a 70K difference would have

Take voltage both sides of the 91K resistor, to me albeit I know little about this circuit that's where I'd start your 2N3565 collector voltage is high and may be having a knock on effect driving the 2N404

It could be something as simple as a dodgy solder joint

 

[megatrav]

Is that rust on top of your 2N404?

Your transistors aren't biasing correctly looking at your voltages, did you try tepee'ing a 67K to the 680K as I said I don't know what effect a 70K difference would have

Take voltage both sides of the 91K resistor, to me albeit I know little about this circuit that's where I'd start your 2N3565 collector voltage is high and may be having a knock on effect driving the 2N404

It could be something as simple as a dodgy solder joint

Thanks for the input! It is not rust, I think it got a little too close to my iron.
I have a 750k resistor I am going to swap out.
I will also check the voltages on each side of the 91k and see what's up.

To my eyes, my solder joints look good, but I may start checking the wires off board as well.
I appreciate any advice on what I should check.
I want to learn as much as I can so I can be more self sufficient in the future.
I am glad it's a simple circuit

 

[Feral Feline]

It is not rust, I think it got a little too close to my iron.

EDIT: old gif got scratched, here's a new'n'

 

[Mcknib]

As @Feral Feline says it may be toast germaniums are more susceptible to heat damage

I'd test it if you've got a transistor tester or use your dmm

https://vetco.net/blog/test-a-transistor-with-a-multimeter/2017-05-04-12-25-37-07

 

[megatrav]

I just ordered more 2N404a's. I couldn't get a consistent reading from the one installed.

 

[Mcknib]

I just ordered more 2N404a's. I couldn't get a consistent reading from the one installed.

Just checking did you take it out of circuit to test

Also as you know you'd expect a lower fwd voltage with germanium 0.2 to 0.4v ish

 

[megatrav]

Just checking did you take it out of circuit to test

Also as you know you'd expect a lower fwd voltage with germanium 0.2 to 0.4v ish

Yessir I took it out to test. Couldn't get a clear reading on any of the legs. It would jump some but mostly it say -0.0

 

[Mcknib]

Again you probably do this but I'm always a bit more careful with germaniums especially expensive one's so I use a croc clip as a heatsink to protect against possible heat damage like this

If you've any other PNP germaniums or lowish hFE PNP silicons like 2N3906 you could try them whilst you wait