Completed sex kit: No sound from right channel

[mpent]

Hi,

Finished assembly of sex kit last night. After hooking up to speakers I am getting no sound from right channel and the output from left channel is scratchy. Starting with right channel, can you please advise me what to focus on to rectify the issue? I can post resistance and/or voltage measurements later today but assuming it's a soldering issue, wondering if someone can tell me what terminals to focus on. This is my first kit and hoping that the issue is poor soldering. Thanks!!

 

[earwaxxer]

Hey Michael - you have the right idea - check each solder joint - with the kit off, touch each joint. Especially the potentiometer, double check you wired it right. That can get tricky. If you are lucky it will jump out at you what needs to be done. - cheers - Eric

 

[Paul Birkeland]

Were the voltages and resistances spot on?

 

[mpent]

No, not spot on. I will go back through the checks later and resolder those out of range and repost.

 

[Paul Birkeland]

A voltage or resistance that is out of range may be something other than a bad solder joint, feel free to post what you've got and we can point you in the right direction.

-PB

 

[mpent]

Will do. Thanks. Any thoughts on why no sound from right channel?

 

[Paul Joppa]

Will do. Thanks. Any thoughts on why no sound from right channel?

If the circuit is working correctly, then it's somewhere in the input or output wiring.

If teh circuit is not working correctly, then that might be the problem.

That's the reason for asking about the voltages and resistances.

 

[mpent]

Ok. Thanks for breaking that down for me. I will post the numbers later. Thanks again!!

 

[mpent]

Ok, here are the numbers:

Resistance:                                                       

Center pins        104.6, 100.                           
2                          .2                                       
3                          .2.                                       
7,17                      .4, .4                 
8,18                      0
9,19                      1.203, 1.201
12,22                    .5, .4
13,23                      .3, .4
15, 25                    .903, .902
A1,B1                    1.421, 1.430
A3,B3                      .692, .691
A6, B6                    236.1, 218.2

voltage:

1.    205.2
2.    -0.1
3.    0
4.    410
5.      205.2
6,16.  391, 391
7, 17.  .2, .2
8, 18.  0,0
9,19.    .1, .3
10,20.    412, 412
11,21.    373, 374
12,22.    0,0
13,23.    0,0
14,24.    0,0
15,25.    18.3, 17.35
A1,b1.    .3, .5
A2,b2.    366.7, 368.7
A3,b3.      18.32, 17.25
A4,b4.      0
A5,b5.    -97.7, -346
A6,b6.    .506, .473
A7,b7.      3.44, 3.43
A8,b8.    2.8, 2.79
C1.            3.46
C2.            2.704 

 

[Paul Joppa]

Re: "Thanks for breaking that down for me." - I hear you; I also hate to do things when I don't know why!

The numbers at B4-5-6 and A6 look off kilter, especially B5. I suspect at least some solder joint problems. Also, check the 1270 ohm resistor at tube pins 6 and the 150K at pins 5 - are they the right value? (measure with the ohmeter across the two leads). If that doesn't turn up anything, swap the tubes and see if the voltage discrepancy follows the tube.

 

[mpent]

Thanks, Paul. I will heed your suggestions tomorow morning when I'm able to get back in there and follow up here. On the resistor check, am I performing this with power supplied or unplugged?

 

[Paul Joppa]

Measure resistances with NO POWER!! And wait for the caps to discharge. Read the warnings in the manual, between the resistance and voltage checks.

 

[mpent]

Hahahahhahahahha....ok!!!!  Resistor...resistance. Folks, I am not only learning but surviving. Really, thank you.

 

[mpent]

235.5 for resistor at pin 6 and 148.7 at pin 5

 

[Paul Joppa]

That's the 237 ohm resistor that should be in the C4S board; there should be a 1270 at pin 6. And watch the meter scale - if you actually have 150 ohms instead of 150K (=150,000) then it's a problem - this sometimes happens when parts get shipped to us.

If you're lucky, you may have only swapped the cathode resistor (pin 6) and the C4S R1 resistor.  :^)

 

[mpent]

Hmmmm...I did receive the C4S upgrade but did not open it. I guess I should open it up and see if the 1270 is in there. So overall, will resoldering the pins you mentioned and putting in the proper resistor at pin 6 rectify my issue?

 

[mpent]

So the C4S parts pack does not have the 1.27k resistor in there and what was supposed to have been stocked in the sex kit were 2 237ohm resistors. I need to obtain these to swap them out. But Paul, the parts list for the C4s upgrade does not contain 237 ohm resistors just 499ohm and 150kohm resistors so I'm confused.

 

[mpent]

Ok. I'm an idiot. I have the 1.27 resistors. I put them at the wrong terminal. Instead of the 249's I got 237's but Dan says that's fine. So I have to swap places with the 1.27 and 237.

 

[Doc B]

I misunderstood you on the phone. The 237 ohm resistors are very different than the 249K ohm resistors. We will send replacements for both.

 

[mpent]

Oh, ok. Thank you much!