Projects are pilin' up

LRT said:
This is why the tube wasnt lit.

If test across #2 and 7 with the tubes removed what should my reading be to power the EL34?
Click to expand...
AMS is correct, the total heater supply voltage should be 6.3vac. Each and all tube socket pins from the heater supply should be 3.15vac with no more than a (+/-) 10% variance.

Could an instrument cable have been used by accident instead of a speaker cable?


67plexi said:
That would suck if it's arcing between pins #2 and #3. I had a Belton octal socket do that will never use Belton ever again.
Click to expand...
What do you recommend over the Beltons?
 
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syscokid said:
AMS is correct, the total heater supply voltage should be 6.3vac. Each and all tube socket pins from the heater supply should be 3.15vac with no more than a (+/-) 10% variance.

Could an instrument cable have been used by accident instead of a speaker cable?



What do you recommend over the Beltons?
Click to expand...

Belton makes ceramic sockets (not plastic). I would rather use ceramic output tube sockets.
That's my personal preference.
You can get ceramic sockets that fit into the stock cutout.
The plastic or Micalex sockets are OK...

Your socket went bad because of bad contact to the tube pin.
This caused overheating of the pin...and fried the plastic.
But with good contacts, that usually doesn't happen. That is an UN-common failure.

It doesn't look like arcing. It looks like overheated pin.

www.parts-express.com

8-Pin Vacuum Tube Socket Ceramic with Mounting Bracket

8-Pin Vacuum Tube Socket Ceramic with Mounting BracketChassis mount 8-pin ceramic tube socket with mounting bracket. Chassis hole diameter: 1-1/16". Mounting centers: 1-7/16". 8-pin socket includes hoop bracket with two screw forks (screws not included) commonly used in bottom mount...
www.parts-express.com
 
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Good to know that Belton makes ceramic octal. My issue was brand new build the plastic Belton were arcing between the pins
only when the tubes were installed killing the tubes no visual sign of arcing top or bottom I was at my wits end lucky
Pete Cornish helped me solve the issue end of it I killed 22 6L6GC and a box of 50 Belton octal sockets in the garbage
I contacted my supplier they said it was possible Chinese counterfeit were sent from them so they sent a new box of Belton and replaced the 22 6L6GC
Used the new box of 50 no issues and that amp survived 3 1/2 years of world tours my last five builds used Mil Spec ceramic tube sockets $20.00 each
thanks to Steve at Apex JR. I just picked up a Mesa MK3 blue stripe failed power transformer 33 years old replaced it worked fine for 10 hours
then the output transformer failed good news the EVM12L speaker is good just put it in the Green Hornet 3 amp I'm happy.

Green Hornet 3 001.JPG

Green Hornet 3 002.JPG
 
Amp Mad Scientist said:
When the socket burns, it's caused by incorrect speaker load.

For example : set amp on 16 ohms and hook amp to 4 ohm cabinet. This will make the socket arc and burn.
A bad speaker cable can also cause this to happen.

So besides replacing a socket, you need to correct speaker problems also.
Click to expand...
Just checked ohms on both cab and both read 15.8 ohms so it seem those cabs are good. The 1960 has a mono/sterio switch and the 4ohm and 16ohm or 8hom using both jacks.

Could this plate be a potential problem and should i wire in direct jacks eliminating the board?
 
LRT said:
Just checked ohms on both cab and both read 15.8 ohms so it seem those cabs are good. The 1960 has a mono/sterio switch and the 4ohm and 16ohm or 8hom using both jacks.

Could this plate be a potential problem and should i wire in direct jacks eliminating the board?
Click to expand...
Both cabinets are 16 ohm?
The amp is using 8 ohm output for 2 cabinets?
The amp is using 16 ohm out for 1 cabinet?
What speaker cables do you have?

How are you setting it?
How are you running it?
 
Heres how the amp is set from the music store i got it from. I was told not to mess with the settings

20210515_161328.jpg
 
Amp Mad Scientist said:
Both cabinets are 16 ohm?
The amp is using 8 ohm output for 2 cabinets?
The amp is using 16 ohm out for 1 cabinet?
What speaker cables do you have?

How are you setting it?
How are you running it?
Click to expand...
Is my impedance swith supposed to be set to 8ohms for 2 cabs?
 
LRT said:
Heres how the amp is set from the music store i got it from. I was told not to mess with the settings

View attachment 66640
Click to expand...
I can't tell what the switch is set to.
If you are running 1 cabinet, the switch should be set 16 ohms.
If you are running 2 cabinets, the switch should be set 8 ohm.
The cabinets should use the 16 ohm in and the switch on the cabinet should be set to mono.

If you are doing something different, what is it?
 
He's got the switch on the amp set to 16

He's using two cabinets, 16ohm in with both

The switch on the 1960 cab is set to mono
 
mcblink said:
He's got the switch on the amp set to 16

He's using two cabinets, 16ohm in with both

The switch on the 1960 cab is set to mono
Click to expand...
Sounds OK...
There is 2 options on the cabinet for mono. 4 ohm and 16 ohm input jacks.
Use the 16 ohm.

In case you have a 4 ohm amp, the cab has a 4 ohm input.

So, replace your fried socket and everything will be OK.
 
LRT said:
Is my impedance swith supposed to be set to 8ohms for 2 cabs?
Click to expand...

Yes.
2X 16 ohm cabs = 8 ohms.

speaker 1 X speaker 2
----------------------- = total load in parallel
speaker 1 + speaker 2

speaker 1 = 16 ohms
speaker 2 = 16 ohms
16 X 16 = 256
--------------- = 8 ohms
16 + 16 = 32
 
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Amp Mad Scientist said:
Sounds OK...
There is 2 options on the cabinet for mono. 4 ohm and 16 ohm input jacks.
Use the 16 ohm.

In case you have a 4 ohm amp, the cab has a 4 ohm input.
Click to expand...
I know on a lot of Marshalls that have 2 or 3 inputs it will say "16ohm only" on a single input and then the parallels which are " 8 and 4 ohm" The switch on mine goes 8 or 4 ohm and the manual says

One 4 Ohm cabinet, set to 4 Ohms
One 8 Ohm cabinet, set to 8 Ohms
Two 8 Ohm cabinets, set to 4 Ohms
Two 16 Ohm cabinets, set to 8 Ohms
 
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