6AL5 substitute

[vendo81]

I recently bought 2 McIntosh MR55 tuners at a garage sale and one of them has 3 small, black solid state replacements put in the 3 6AL5 tube sockets. They have "IBM 441272" and "Hughes SA 1611" on them. Does anyone know if these are proper replacements? They work in the tuner but I'm just wondering if they are as good as 6AL5 tubes?

[GordonW]

I've seen solid-state replacements for power rectifiers, but never for a "signal" diode such as a 6AL5.

Seems like, with the inexpensive nature of 6AL5s, solid-state replacements would be sort of a "fools errand"... one would wonder why these even exist...

Regards,
Gordon.

[cademan]

The 6AL5 tube is just a detector (signal) diode. If the replacement parts work, someone knew what they were doing and probably didn't have a 6AL5 on hand. If you're uncomfortable with the replacement, just unsolder them from the circuit and replace with 6AL5 tubes. I have a ton if you're interested, just PM me.

[gadget73]

6AL5 is a twin diode tube, probably not hard to replicate with SS parts but like Gordon said, not much point either. I've also got a bunch of them, they're very common in later FM sets and TV sets as the FM detector.

[electroking]

In some TV sets, they were used as the horizontal phase detector, and
manufacturers would sometimes substitute a pair of SELENIUM diodes for
the 6AL5 tube. I have always wondered why selenium was used.

[gadget73]

maybe to simulate the voltage drop that the tube would have ?

[vendo81]

Thanks for all your replies and THANKS Cademan for your offer. I went though some of my boxes of tubes and found a few. These must be very common :yes:

[GordonW]

These must be very common :yes:

This is DEFINITELY true. :thmbsp:

Anyone who parts out old junk radios will wind up with a plethora, as they hardly ever seem to die, IME...

Regards,
Gordon.