Can an EZ80 be substituted for an EZ81 in a guitar amp without
frying anything?

"Joe Schmo"

Can an EZ80 be substituted for an EZ81 in a guitar amp without
frying anything?




But I'm a substitute for another type

I may look pretty tall but my pins are high

The simple things you see are all complicated

I look pretty young, but I'm just back-dated, yeah



P Townshend





............ Phil

Hi Joe ,

An EZ81 has higher heater current than the EZ80 .
So as long as you power trannie is up to that , no problem .
Maybe you'll get 5V more B+ , that's all I think .

Ronald .


"Joe Schmo" schreef in bericht
...
Can an EZ80 be substituted for an EZ81 in a guitar amp without
frying anything?

On Sat, 12 Mar 2005 06:45:43 +0000, Joe Schmo wrote:

Can an EZ80 be substituted for an EZ81 in a guitar amp without frying
anything?

Not necessarily.
EZ80 6.3v 0.6A heater. 90mA max output.
EZ81 6.3v 1.0A heater. 150mA max output.
It depends on your amp!

--
Mick
(no M$ software on here... :-) )
Web: http://www.nascom.info
Web: http://projectedsound.tk

mick wrote in
news
Not necessarily.
EZ80 6.3v 0.6A heater. 90mA max output.
EZ81 6.3v 1.0A heater. 150mA max output.
It depends on your amp!


The amp is a Marshall Handwired 1974x re-issue.

Here's the schematic (which is all hieroglyphics to me) that
should be very close to my re-issue:

http://18watt.com/Storage/0riginal%2...8w%20schiz.jpg

Thanks, -Barry (Joe Schmo's my pen name)

"Phil Allison" wrote in message
...

"Joe Schmo"

Can an EZ80 be substituted for an EZ81 in a guitar amp without
frying anything?




But I'm a substitute for another type

I may look pretty tall but my pins are high

The simple things you see are all complicated

I look pretty young, but I'm just back-dated, yeah



P Townshend





........... Phil


Shutup.
**** you.
-Killdozer

"Joe Schmo" wrote in message
...
Can an EZ80 be substituted for an EZ81 in a guitar amp without
frying anything?
Joe, I can send you an ez80 for the price of shipping (used, good)
-dim

On Sat, 12 Mar 2005 17:19:30 +0000, Joe Schmo wrote:

snip

Here's the schematic (which is all hieroglyphics to me) that should be
very close to my re-issue:

http://18watt.com/Storage/0riginal%2...8w%20schiz.jpg


Going off that I think you would just get away with a EZ80, but you are
pushing it over the limit if you run at full output. That will, at least,
shorten its life quite a bit. I suspect that there is also insufficient
series resistance to keep an EZ80 happy. You would be better sticking with
an EZ81 if you can - it will be run within its ratings.

--
Mick
(no M$ software on here... :-) )
Web: http://www.nascom.info
Web: http://projectedsound.tk

"shiva"

"Phil Allison"

"Joe Schmo"

Can an EZ80 be substituted for an EZ81 in a guitar amp without
frying anything?



But I'm a substitute for another type

I may look pretty tall but my pins are high

The simple things you see are all complicated

I look pretty young, but I'm just back-dated, yeah


P Townshend



Shutup.
**** you.
-Killdozer



** Cancer is too good for a someone as totally brain ****ed a "shiva".





............... Phil

mick wrote in
news
On Sat, 12 Mar 2005 17:19:30 +0000, Joe Schmo wrote:

snip
[...]

Going off that I think you would just get away with a EZ80,
but you are pushing it over the limit if you run at full
output. That will, at least, shorten its life quite a bit.
I suspect that there is also insufficient series resistance
to keep an EZ80 happy. You would be better sticking with
an EZ81 if you can - it will be run within its ratings.


Good advice... I think I'll take it. I have a NIB Mullard EZ81
or two laying around somewhere I think I'll just use that.

Thanks for the info, it's much appreciated.

-Barry

"Joe Schmo" wrote in message
...
mick wrote in
news
On Sat, 12 Mar 2005 17:19:30 +0000, Joe Schmo wrote:

snip
[...]

Going off that I think you would just get away with a EZ80,
but you are pushing it over the limit if you run at full
output. That will, at least, shorten its life quite a bit.
I suspect that there is also insufficient series resistance
to keep an EZ80 happy. You would be better sticking with
an EZ81 if you can - it will be run within its ratings.


Good advice... I think I'll take it. I have a NIB Mullard EZ81
or two laying around somewhere I think I'll just use that.

Thanks for the info, it's much appreciated.

-Barry

The "B" part of NIB is particularly important. I have a collection of "B"s,
for the folks who like that sort of thing.
P.S. It was standard practice in ma & pa TV repair stores to swap out
tubes which the tech suspected to be bad, and, if the problem wasn't
solved, to simply stick the old tube into the box, (usually) correctly
assuming that the tube was fine, and the problem lay elsewhere.
It was (and presumably is - though the pickins' must be mighty slim) for
goofs like me to go on cross - country shopping sprees, stopping at every
lil' (hopefully on it's last legs) TV repair shop, and asking them to look
at their stock of tubes, offering them cold, hard cash for entire lots if
there were a few gems in it.
Everyone has quickly learned to open the boxes on the spot, after pulling
out dusty old tubes from fresh new boxes, often with a different brand. At
times, the boxes were simply empty. No attempt at deception, the TV guys
simply didn't anticipate the audiophools - a toob which measured well was a
new tube, as far as they were concerned - shoo' got them sets up & going.
Now there's a new gimmick - *unopened* NIB. Shhesh. Talk abouut a pig in
a poke...
I still took all the boxes, though, if they looked neat - I don't sell
tubes, so, again, no deception intended on my part - I just dig old graphics
& packaging jobs (there (was) a TV replacement parts co which had a truly
Satanic goat on a lightnin' bolt background - how cool's *that*?), and I
collect logos from RCA to heathkit (the headstocks of most of my custom
guitars had either enameled RCA logos cut out from old RCA scopes, or, with
the latest gibsonesque chambered set-neck, a plastic "heathkit" script), so
i do it for kicks). Others are not that scrupulous. I'd rather get pulls
from old mil / lab surplus gear, which has never *seen* power, than pay for
the "NIB" exotica of questionable origin.
-dim

"shiva" wrote in
news:7DiZd.2377$qN3.2350@trndny01:


"Joe Schmo" wrote in message
...
mick wrote in
news
On Sat, 12 Mar 2005 17:19:30 +0000, Joe Schmo wrote:

snip
[...]

Going off that I think you would just get away with a
EZ80, but you are pushing it over the limit if you run
at full output. That will, at least, shorten its life
quite a bit. I suspect that there is also insufficient
series resistance to keep an EZ80 happy. You would be
better sticking with an EZ81 if you can - it will be run
within its ratings.


Good advice... I think I'll take it. I have a NIB Mullard
EZ81 or two laying around somewhere I think I'll just use
that.

Thanks for the info, it's much appreciated.

-Barry

The "B" part of NIB is particularly important. I have a
collection of "B"s, for the folks who like that sort of
thing.
P.S. It was standard practice in ma & pa TV repair
stores to swap out
tubes which the tech suspected to be bad, and, if the
problem wasn't solved, to simply stick the old tube into
the box, (usually) correctly assuming that the tube was
fine, and the problem lay elsewhere.

snip

I'd rather
get pulls from old mil / lab surplus gear, which has never
*seen* power, than pay for the "NIB" exotica of
questionable origin. -dim


Umm, I'm sure this is all true in many cases, and I do have a
lot of "pulls" too, but my NIB's in this case are still in
boxes sealed by their original plastic wrap. They're unopened.
Doesn't mean they're good "toobs" just means they're NIB...