I have two piece of equipment that use the 5Y4 as a full wave rectifier and have to spares on hand. I just purchased a piece of equipment which uses a 5Y3 as a full wave rectifier. The information that I have on the tubes indicates plate voltage 350-0-350V for both and Ir 125 for both. Pin Out is different but that's a one time change over. Also, 5Y3 sell for $10.00 plus while 5Y4 $6.00 plus. Will this work? Does anyone have any cautionary comments? PL

Hi

5Y3 and 5Y4 are electrically the same. There is a small change you can make so either tube will operate.

Jumper between pin #3 and #4.

Jumper between pin #5 and #6.

Jumper between pin #2 and #7.

With these changes either tube can be used in the socket. Be sure the original socket is good. There will be high voltages between adjacent pins.

Norm

: I have two piece of equipment that use the 5Y4 as a full wave rectifier and have to spares on hand. I just purchased a piece of equipment which uses a 5Y3 as a full wave rectifier. The information that I have on the tubes indicates plate voltage 350-0-350V for both and Ir 125 for both. Pin Out is different but that's a one time change over. Also, 5Y3 sell for $10.00 plus while 5Y4 $6.00 plus. Will this work? Does anyone have any cautionary comments? PL

Norm, thank you very much. That is cool, I can still revert to original tube at any time. I'll carefully inspect socket for any chance of shorts. PL

:Hi
:
: 5Y3 and 5Y4 are electrically the same. There is a small change you can make so either tube will operate.
:
: Jumper between pin #3 and #4.
:
: Jumper between pin #5 and #6.
:
: Jumper between pin #2 and #7.
:
: With these changes either tube can be used in the socket. Be sure the original socket is good. There will be high voltages between adjacent pins.
:
:Norm
:
:: I have two piece of equipment that use the 5Y4 as a full wave rectifier and have to spares on hand. I just purchased a piece of equipment which uses a 5Y3 as a full wave rectifier. The information that I have on the tubes indicates plate voltage 350-0-350V for both and Ir 125 for both. Pin Out is different but that's a one time change over. Also, 5Y3 sell for $10.00 plus while 5Y4 $6.00 plus. Will this work? Does anyone have any cautionary comments? PL

That is why you will notice the pinout of the 5Y3 and 5Y4, and 5U4, and many other octal rectifiers of this type as being very similar to the 4 pin #80 tube. The pins are spread out evenly from eachother, with a pin between to prevent arcing. If your socket is in good order, though, you shouldn't have troubles.

T.

Thank you for the replies, just today opened unit up, someone had changed socket to four pin and an 80 is in there. I haven't checked prices on 80's but think I'll change it socket back to octal and wire for the 5Y3 and 4. It will be new socket, phenol. Should I buy a ceramic? Tom, funny you mentioned the 80. PL

:That is why you will notice the pinout of the 5Y3 and 5Y4, and 5U4, and many other octal rectifiers of this type as being very similar to the 4 pin #80 tube. The pins are spread out evenly from eachother, with a pin between to prevent arcing. If your socket is in good order, though, you shouldn't have troubles.
:
:T.

: Thank you for the replies, just today opened unit up, someone had changed socket to four pin and an 80 is in there. I haven't checked prices on 80's but think I'll change it socket back to octal and wire for the 5Y3 and 4. It will be new socket, phenol. Should I buy a ceramic? Tom, funny you mentioned the 80. PL
:
:
::That is why you will notice the pinout of the 5Y3 and 5Y4, and 5U4, and many other octal rectifiers of this type as being very similar to the 4 pin #80 tube. The pins are spread out evenly from eachother, with a pin between to prevent arcing. If your socket is in good order, though, you shouldn't have troubles.
::
::T.

Well this is a fine howdy do. The schematic for this unit shows a 5Y3, I have 5Y4s ergo my post. Now I look at the set and the chassis layout diagram and it shows an 80! I checked and 80 is electrically the same as 5Y3 & 4, but now I will have to change the socket. PL