"Flying saucer" style diodes?

[Rhodesplyr]

I've run across a few "flying saucer" style diodes in equipment made ~1960-65. If you've seen one, you know what I'm talking about.

If they're still apparently working fine, would you leave them where they are, or are they something that should automatically be replaced for the sake of reliability?

[Enzo]

I guess I don't know what you refer to. And honest, I was building amps back then.

[Techknowman]

Do they look like these



OR

[Rhodesplyr]

Here's a photo of them. I didn't know they were that unusual, but, then again, I've only seen them twice, once in my Farfisa Compact Duo and once in this 1961 Leslie amp. If Enzo has never seen these, I will be surprised.

[Enzo]

I've seen lots, but I don;t recall those specifically. They are not seleniums, so there is 90% of the trouble gone right there. Measure the junction drop with a meter to see if they are silicin or germanium. Is there a type number on the Leslie print? Or the Farfisa for that matter?

[ken]

I've seen those myself, I think they are early silicon power diodes. I'd replace them myself, if only for the peace of mind.

ken

[Rhodesplyr]

They're definitely silicon. On the Compact Duo schematic, it's a 2E05.

In the Leslie 22H and 47 manuals, it's just "silicon rectifier." In the 1963 Leslie 147 manual, its an 800PIV 1A silicon diode. Leslie started out using two in series for each side of the bridge, but by the end of the 60s, they were just using one diode per side.

[Jazz P Bass]

Here are the specs.
Category » Diodes
Class » Silicon Rectifiers
Type » General-Purpose
2E05 Specifications
Military/High-Rel : N
I(O) Max.(A) Output Current : 2.0
@Temp (шC) (Test Condition) : 75#
V(RRM)(V) Rep.Pk.Rev. Voltage : 50
I(FSM) Max.(A) Pk.Fwd.Sur.Cur. : 50
V(FM) Max.(V) Forward Voltage : 1.3
@I(FM) (A) (Test Condition) : 2.0
@Temp. (шC) (Test Condition) : 25#
I(RM) Max.(A) Reverse Current : 2.0u
@V(R) (V)(Test Condition) : 50
I(RM) Max.(A) Pk. Rev. Current : .05m
@Temp. (шC) (Test Condition) : 100
Maximum Operating Temp (шC) : 150#
Package Style : Axial-5
Mounting Style : T


Read more: 2E05 Spec Sheets Details Diodes, Transistors, Thyristors, Triacs, Diode Array, Integrated Circuits and Semiconductors — Product Line

[diagrammatiks]

they look like boobies.

[Rhodesplyr]

Jazz, thanks for the information. The diode in the Farfisa was for a 9V DC supply.

The ones in the Leslie are in the same package, but they are for a bridge supplying B+ 440V DC.

I wonder if they were made in Europe since I've never seen an American-made original component in a 1960s Farfisa.

[km6xz]

They were never used in the US as OEM as I recall, just Europe. There is also a similar style case in Eastern Europe. Leave 'em in, no normal expiration date and are probably overkill.

[Steve Conner]

they look like boobies.

And, they have silicon implants!

[J M Fahey]

I remember the ones which were full metal case, meaning the metallic disk here plus a "hat" shaped metal cover.
And then we had the full plastic ones, such as 1Nxxxx .
These look like the missing link: silicon chip mounted on the metal disk, but sealed with a drop of epoxy.
Should be good forever, unless abused.

[rich-d]

rectifiers out of my 1970 univox,, i thought they were caps when i first seen them, lmao

[1ampman]

If there in equipment not used much or need to be reliable , leave them. If it's something you have to count on or need up to specs, then replace..... especially if your recapping the supply. .... Even if they're working, the glue that seals them and holds them together is suspect...