• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

What do you think..OP Tx

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Look at the physical size and then ask yourself, how much sound can go through a transformer that is not much bigger than a 12AX7.

I have an older set from the same manufacturer that doesn't have the 8K tap. They work for the intended application, a cranked guitar amp with a small speaker, not much else.

If you are going to get OPT's from the US, get the Edcor XSE15-8-5K, they will blow those little "Champs" away in a HiFi application. For 2 or 3 watts they are great. I use a set in a SE trioded 6V6GT. Juts about right. Saturation sets in when you plug in a KT88 and ask for 8 watts.
 
Anything from the USA has become uneconomic due to postage and import duties.
It is better to source from EU countries ie Valves Stuff or RITTER electronic systems--Die Röhrenspezialisten seit 30 Jahren! - these are good BUT be aware that they will only accept payment via IBAN. A general problem in Germany.
A good site that accepts PayPal is Tube-Town - Hot Stuff cool sounds - excellent service

Cheers

John
Hi Cookj ! I was having a look to this RITTER electronic systems, and they sell output transformers at very good prices, but i dont know the quality of this transfos ! Did you ever tested one of those ? Can you tell me something about the quality ? Thanks
 
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Just for interest..

Regards
M. Gregg
 

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Well,

after looking at a few other makes of OP Tx...edcor has better low frequency..I'll use Hammond mains..(Keep the weight down)

Then whats in the box ?(rectifier) 5y3...It can be used horizontal if the pins 2/4 are vertical...I'll try and get it upright...
NB its an all valves/Tx's mounted in the box build I hope.. :)

A couple of Mullard EF86 (Paint missing from a quick wash) should last about 35seconds to 20 years dependant upon power up..:D Sylvania 5Y3..about the same..:D (Then again the 5Y3 is new so maybe it will last a bit longer)

Regards
M. Gregg
 

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Some parts,

Arrived today...

I had to try the strange red astron just to find out what tin sounds like..:D
I have some same value jensens and others to try for fun..

Tx's on order..Hammond mains, edcor output..
Suppose I will have to do some more on it now..:rolleyes:

Regards
M. Gregg
 

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Disabled Account
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More from the snail...:snail:

Power Tx arrived..
Its big enough to mod if I want to...hopefully it will run cool/quiet..:xfingers:

Vent holes drilled in base plate..

Just thinking about bases for the EF86's..I will use shrouded then I have the choice to use screening cans..I like the phenolic..But I'll get both. :D


Regards
M. Gregg
 

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Some more....:snail:

Started to build the input selector board.
Waiting for some more parts.

Just thinking about some mundorf tubecaps...however I have to wait for the OP Tx's from Edcor to check the space available.

Regards
M. Gregg
 

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Disabled Account
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Selector card completed,

I have some anti vibration mounts for the circuit board.
:snail: <<<still fitting it in...:) so its a bit slow..

I don't want to use PCB tracks so its silver wire link.

Regards
M. Gregg
 

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