course /study / learning electronics

[RitzRed]

I am new to tube amps and electronics I was an electrician but am retired now .Does anyone know a crash course I can take to give me the basics of electronics. What I need to know right now is what the different tubes do like what is the difference between 6L6 tubes and 6V6 is there something that tells the different functions of different tubes.

[Jazz P Bass]

That is a far leap
From basic electronics to how a tube works.
Welcome to the world of 'Solder Sniffers'.
First off, there is a reason for each tube.
Just as there is a reason for different transistors.
The 6V6 & 6L6 tubes are power tubes.
There is very little voltage amplification but they are very good at delivering power to a load (P=V x I)
The 6V6 is rated to deliver x amount of power to the output transformer.
At a rated voltage, output configuration, load.
The 6L6, generally, is capable of more.
And in being capable of 'more', it requires more.
A larger power supply capability, a different bias arraingement, a different output transformer.
That is my 'nutshell'.
I hope it helps.

[RitzRed]

Yes it does help very much ! It tells me that just changing the tubes won,t work without changing allot of other things of witch I am not in the know (YET) here is a pic of one of the little amps I am wanting to make into a harp amp it is a Magnavox, It is the one with 2 50EH5 tubes and one 9 pin tube with the numbers/letters are gone what tube do you think it is it is shorter and bigger around than the 2 50EH5,s

[Jazz P Bass]

That appears to be a 'stereo' amp.
2 channels utilizing a 50EH5 output tube.
Each 50EH5 has an output transformer attached.
The small tube could be a number of different tubes.
You would have to trace out (draw) the existing circuit to narrow it down.
"Most probably' it is a twin triode type (12AX7).
As this is one component of a complete system, there is a lot missing.
I do not see a power supply.
There is a capacitor but that is all that is shown from the top.
There are not any controls.(Volume, Tone).
All in all it looks like a lot of work as there are very few useable components.

[tboy]

I do not see a power supply.

50EH5 suggests a line powered design, so you wouldn't see a power transformer. Adding an isolation transformer would be in order.

[RitzRed]

.no there are tone and volume controls on it I will take a better picture of it and put it on here next time. Where do I get the values when looking for a isolation transformer I found some on ebay that are allot smaller than the ones they sell at the electronics store you pointed me to I just don,t know witch one to buy so is there a volt combo that I should look for

[RitzRed]

I found some isolation transformers on eBay that are allot better price would you please look at eBay at these item numbers and then tell me if one or more of them will work on these little amps the first item number is 150919162905, next 121006972437,next 110931824117 I would really appreciate it thanks these are the amps I am dealing with.as you can tell I really don,t know anything about electronics if I knew the rating of the amps I could probably figure out the right isolation transformer