Just got my new Marstan trannie and gonna need some help

[harris51]

Can anybody tell me where are the high voltage leads on this transformer it's the 1202-55 and Im sure ill be asking many more question about these transformers Thank in advance for once again saving my butt!

[harris51]

has anyone used these Radio spares from Marstan and can anyone provide any layouts? Thanks

[Colossal]

The two red leads marked HT (stands for the classical High Tension) are the high voltages secondaries. You also need the red/yellow lead marked Ground. That is the high voltage center tap to ground.

Stay safe!

[ToneMerc]

has anyone used these Radio spares from Marstan and can anyone provide any layouts? Thanks

http://www.marstran.com/Wiring%20Diagrams.html

TM

[harris51]

the high voltage (ht) taps are on the same side as the heaters as opposed to the metro trannies is that normal? please excuse the dummy questions and there will be more

[ToneMerc]

the high voltage (ht) taps are on the same side as the heaters as opposed to the metro trannies is that normal? please excuse the dummy questions and there will be more

Not being a smartass here, but it's normal for a Marstran. On the surface it just means you won't have HT leads terminating near the front of the chassis and traveling along the side of the chassis toward the rectifier tube.

TM

[harris51]

Thank you tone merc

[harris51]

I trying to get activated to the Marstran forum I guess there busy over there. Im sure Ill have alot of questions hooking the output tranny, till then
thanks a bunch!

[harris51]

running the amp at 8 ohms (2-16 ohm speakers) which are my primary output tranformers wires?

[ToneMerc]

IMHO, the tag board type RS are easiest to wire. Although I believe MM does offer an " easy wire" version. Neverthless, do a google search, there's info on on the web on how to wire these to a couple od switch options.

TM

[martin manning]

running the amp at 8 ohms (2-16 ohm speakers) which are my primary output tranformers wires?

What primary impedance do you want to run? With the secondary wired as shown you have three options available, all matching to 8 ohms. FWIW, the original JTM45 used 8k primary for KT66's.

[harris51]

Im want to run the amp at 8ohms being that i have two 16 ohm speakers.

[harris51]

so what i hearing from you and seeing on the chart i would wind the 8k wire(brown) and the other 8k wire (brown/w white stripe) and those two would go to v4 and v5?

[JazzGuitarGimp]

Im want to run the amp at 8ohms being that i have two 16 ohm speakers.

Hi Harris51,

Martin is asking you what primary OT impedance you desire. You have answered with the secondary impedance. If you do not know what primary impedance you want, tell us about the output tubes: part number and quantity, as well as your expected B+ voltage, and a description of how you want the amp to sound, and you might get a relevant answer.

Good luck!

[martin manning]

so what i hearing from you and seeing on the chart i would wind the 8k wire(brown) and the other 8k wire (brown/w white stripe) and those two would go to v4 and v5?

I don't know what you mean by "wind," but yes the ones marked 8k are the ones to use for 8k primary impedance. The diagram doesn't give any phase information, so you will have to guess, and be prepared to swap the Brown and Brown/White leads if it howls. You will probably want to try 6k6 too, and decide which you like better.