Hi to all,

I own a Philco 38-10

It has a 6K7G in the IF stage.
Tube are not good.

I took temporary one good 6K7G from another good set i have. Then my Philco worked very well. Alignment has been done properly.

So i decided to make a replacement. I tried to replace the 6K7G by a metal 6K7 which has (i think) the same pin-out in my Philco model:38-10, but for some reasons, it doesn't work.
I tried to re-align the IF without success, i hear some sort of motorboating.

Question is: Why it is not possible to directly replace a 6K7G by a metal 6K7 ?
Are they so different ?

Is there anything i could modify to make my Philco 38-10 working with a 6K7 ?

Do you believe i could have better results with a 6SK7 (after re-wiring the socket of course) ?

Thanks
Vianney

:Hi to all,
:
:I own a Philco 38-10
:
:It has a 6K7G in the IF stage.
:Tube are not good.
:
:I took temporary one good 6K7G from another good set i have. Then my Philco worked very well. Alignment has been done properly.
:
:So i decided to make a replacement. I tried to replace the 6K7G by a metal 6K7 which has (i think) the same pin-out in my Philco model:38-10, but for some reasons, it doesn't work.
:I tried to re-align the IF without success, i hear some sort of motorboating.
:
:Question is: Why it is not possible to directly replace a 6K7G by a metal 6K7 ?
:Are they so different ?
:
:Is there anything i could modify to make my Philco 38-10 working with a 6K7 ?
:
:Do you believe i could have better results with a 6SK7 (after re-wiring the socket of course) ?
:
:Thanks
:Vianney
:
:
Vianney,

When using a metal tube make sure that pin one is connected to ground.

Mitch

::Hi to all,
::
::I own a Philco 38-10
::
::It has a 6K7G in the IF stage.
::Tube are not good.
::
::I took temporary one good 6K7G from another good set i have. Then my Philco worked very well. Alignment has been done properly.
::
::So i decided to make a replacement. I tried to replace the 6K7G by a metal 6K7 which has (i think) the same pin-out in my Philco model:38-10, but for some reasons, it doesn't work.
::I tried to re-align the IF without success, i hear some sort of motorboating.
::
::Question is: Why it is not possible to directly replace a 6K7G by a metal 6K7 ?
::Are they so different ?
::
::Is there anything i could modify to make my Philco 38-10 working with a 6K7 ?
::
::Do you believe i could have better results with a 6SK7 (after re-wiring the socket of course) ?
::
::Thanks
::Vianney
::
::
:Vianney,
:
:When using a metal tube make sure that pin one is connected to ground.
:
:Mitch
:
You will need to also be sure that pin 1 of the tube socket is not used as a 'tie' point for other circuitry if using a metal tube. John

Hi,

Thanks for the tip.

Pin one was not grounded.
In fact there was no lug installed on pin 1 of the socket.
I have been force to replace the socket.

Radio play well now with a 6K6 and pin 1 to GND

Thanks
Vianney