Studio Projects T3 circuit

[atomdog]

Hi guys,

What a strange coincidence !!

I decided to replace the power supply caps and had a question only to find this mic is being discussed as a live topic.

Mine is a first gen tb-1.

Im currently awaiting parts so I can replace the in/out entirely with better wire and noticed the 2 ceramic 0.1uf caps hardwired to the output socket. (Second pic)

Do I really need to copy this or can I omit them entirely ?

Thanks.

 

[Emmathom]

Hi @atomdog
Usually we see 2*10nF at XLR to supress RF noise... Note that @LevinGuitar said that its TB1 PSU's were noisy : maybe it's the opportunity to "refreh" all solders and check every connexion, etc... LM7806 can be noisy too ! But no other way to do without changing the whole thing.
For my part, not having a PSU, I have to build one from scratch but with HV & heater regulations.

Can you please provide a pict of the front pannel so one can read the XLR pins wiring ?
BR

 

[Khron]

Can you please provide a pict of the front pannel so one can read the XLR pins wiring ?

Have you considered even / at least a quick Google (image) search?

 

[Emmathom]

The modified PSU and the circuitry schematic for my TB-1.
Tube is 12AY7 NOS. Anode is 120v@1,5mA. Capsule polar. is 71v. Heater is elevated +25v.
Will use the unused wires (3 free) to supply the heater and HV minus into inside the mic.

 

[Emmathom]

PSU done and tested... Waiting for the 7 pins XLR to be delivered.

I've installed a self timer circuitry which switches HV on (and lighten the white led) about 1mn45" after heater.

It was tough to fit the 15cm x 10,5cm x 5,5cm enclosure but it's done with success. I wanted to keep these dimensions for the PSU to fit in the Studio Project original case.

Now I've got to work on the mic itself...

 

[thor.zmt]

PSU done and tested... Waiting for the 7 pins XLR to be delivered.

I've installed a self timer circuitry which switches HV on (and lighten the white led) about 1mn45" after heater.

It was tough to fit the 15cm x 10,5cm x 5,5cm enclosure but it's done with success. I wanted to keep these dimensions for the PSU to fit in the Studio Project original case.

Now I've got to work on the mic itself...

Nice work!

 

[Emmathom]

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