Hi Everyone, I am trying to use a 6E5 as a substitute for a EM4 used in a Mullard 98 ( Same as Philips 4462 ). The original tube broke loose from its base with the base still stuck in the socket which refuses to come out even though I broke a lot of the valve base with some bits still in the socket.
I wired it up as per the data sheet but I get no glow on the target anode.
Has anybody done work with this tube and if so do you have typical voltage measurements,
The tube was bought new from HRSA tube store.
Thanks for any advice.
Roger.

Provided Pin 5 is GND, pin 4 is B+ of anywhere between 125 and 250 volts and there is 6.3VAC between pins 1 and 5, the target should light.

The rest just affects the eye angle.

The RCA datasheet is good....

https://frank.pocnet.net/sheets/049/6/6E5.pdf

Er - I assume you are counting the pins from underneath the socket, clockwise from pin 1 which is the LH thick pin.

Thanks for the input Ian,

I'm using an octal based version ( 6E5C )but have double checked the connections. I have 250 volts.
I'm going to try using a 9 volt battery and pot to see if I can find a range of control grid where I get a glow on the target anode.Will let you know how it goes.
Roger.

Right, a Russian 6E5C is not a 6E5.

The EM4 has a Philips P-base. Valves with this base are notorious for getting stuck in the socket, or breaking off when attempting to remove. It was a bad idea at the time and should never have existed.

Anyway, I assume you had to remove the socket and use an octal one in its place.

EM4 - 6E5C

Heater - 2,3 - 2,7
Cathode - 4 - 8
Grid (from AGC) - 6 - 5
Target - 7 - 6
Deflector anode - 5 - 3

The EM4 has 2 displays but the 6E5C only has one, so forget about what's originally on pin 8 of the Philips socket.

The resistor on pin 5 (originally 470k or 1 Meg or more) will most likely be open circuit so it will have to be replaced.


Now that you've done the wiring up, is the heater alight? If so, there's only 3 more pins to check.

Ooooops..!!
I was working in my garage with the door open = high ambient light....so I couldn't see that it was working all the time..!!
Door closed and cardboard packing tube on the valve....there it was, a nice variable "V" as tuning through a station.
Thanks for all your interest and advice and lesson learned..!!
Roger,