Amplion Convette MOD LC4

[Andrew Humphriss]

Does anyone have a circuit diagram for the above or any data on same?
Should the LT be 4.5v
and HT 150v?
Another e-bay purchase
Andrew 2E0NDZ

[Cobaltblue]

The majority of these Convettes have the voltage written on them.

The output voltages will be high with no load due to the high internal resistances of the rectifiers and chokes.

I am guessing it should be 1.5 and 90V

It should state at what current the majority were for simple 4 valve sets wher the total LT was either 125mA or 250mA the later D*96 were half the filament current of the D*91/2 valves.

Some were made for specific sets due to the battery space available.

A picture as always will help.

Cheers

Mike T

[Andrew Humphriss]

Hello Mike
nothing marked on the PSU yes the voltage is off load, I could do with a circuit diagram. Andy

[cathoderay57]

Not the same model number as yours but the circuit does provide a 4v output https://www.vintage-radio.net/forum/...ad.php?t=92216

[Cobaltblue]

To my knowledge the only circuit for a Convette I have seen is for the M2V

They all use pretty much the same circuit, but models like the MV2 were designed for 2V battery valves whereas most were designed for all dry battery portables.

There is a mention on the Radio Workshop which says the DB3 is similar to the MV2 but without a meter, its true the circuit is similar but the voltages and the usage are different.

The filament circuit has a centre tapped winding, I think its about 3V-0-3V feeding a full wave Metal oxide rectifier. The output goes to a smoothing cap then through a smoothing choke to a second capacitor. Off load you will get around 4V

Indeed as with all the All dry Convette's the radio needs to be on before you apply power to the Convette or you will stress the filaments.

You can tell a lot by the sockets, If it has a single large 4Pin (B4 size) then its probably for 250mA filament supply.

Yours maybe similar to the HL4 but without the current selector?

https://www.radiomuseum.org/r/amplion_convette_hl4.html

A picture would be nice I have quite a few Convette's including the PRI PRI but don't recall coming across this one.

Cheers

Mike T

[Phil G4SPZ]

I have a circuit for the MV2-B which may or may not help you.

Phil

[AC/HL]

Originally Posted by Cobaltblue

Some were made for specific sets due to the battery space available.

A picture as always will help.

Originally Posted by Phil G4SPZ

I have a circuit for the MV2-B which may or may not help you.

This seems to be the only easily available data on the net, but yours is probably similar enough to reverse engineer.