HELP..COLLINS 30L-1
 

I hope that I can get some ideas of my problems with my
30L-1...It was out of use for awhile, and I brought it up very slowly,
and all lookes fine..worked for about a day, but now when I drive it
even lightly, and dip the final with the tune control and very light
loading, even with very minimal drive, it pops the primary fuse...DC
voltage appears fine, and there doesn't seem like a lot else that can
go wrong...Could it be the 811A-s, and would it be possible to try to
prove that by running only one 811a at a time??? I'll be watching the
thread for any and all suggestions........Thanks......Bob

"Edward Knobloch" wrote in message
news:i5wrd.5114$_E3.4107@trndny06...
wrote:
I hope that I can get some ideas of my problems with my
30L-1...It was out of use for awhile, and I brought it up very slowly,
and all lookes fine..worked for about a day, but now when I drive it
even lightly, and dip the final with the tune control and very light
loading, even with very minimal drive, it pops the primary fuse.snip
Hi, Bob

It's not wise to operate the 30L-1 at minimal loading
(loading capacitor maxed) - you will run excessive grid current.
Tune up with a small amount amount of drive, using the tune meter,
per the manual. Then, run a reduced amount of drive if you want to keep
the power low.

I was there when a friend tried running his new
30L-1 on RTTY, by keeping the loading capacitor maxed.
After a few minutes, we smelled something burning. (I think
it was the 2W grid resistor R-28 overheating).
It spooked him about the 30L-1.
He later sold it (to me) and bought a Henry 3K.

Some 811A tubes are not suited for operation in horizontal mounting.
The plane of the filament structure should line up with the two
thick pins of the tube base for the tube to be OK in horizontal operation.

73,
Ed Knobloch

See that big black strip on the meter? Thats tune position. Run 20 to 25
watts of drive from the exciter. Try tuning the plate and load so it is
even with that mark.

If it has been sitting around a while you may have problems in the
electrolytics.

If you tuned it up with high drive, and had the cap maxed out you may indeed
have blown the grids out of a 811 or two.

If you did they will 'rattle' and you may be able to see some trash in the
tube rolling around.

Dan/W4NTI

"Edward Knobloch" wrote in message
news:i5wrd.5114$_E3.4107@trndny06...
wrote:
I hope that I can get some ideas of my problems with my
30L-1...It was out of use for awhile, and I brought it up very slowly,
and all lookes fine..worked for about a day, but now when I drive it
even lightly, and dip the final with the tune control and very light
loading, even with very minimal drive, it pops the primary fuse.snip
Hi, Bob

It's not wise to operate the 30L-1 at minimal loading
(loading capacitor maxed) - you will run excessive grid current.
Tune up with a small amount amount of drive, using the tune meter,
per the manual. Then, run a reduced amount of drive if you want to keep
the power low.

I was there when a friend tried running his new
30L-1 on RTTY, by keeping the loading capacitor maxed.
After a few minutes, we smelled something burning. (I think
it was the 2W grid resistor R-28 overheating).
It spooked him about the 30L-1.
He later sold it (to me) and bought a Henry 3K.

Some 811A tubes are not suited for operation in horizontal mounting.
The plane of the filament structure should line up with the two
thick pins of the tube base for the tube to be OK in horizontal operation.

73,
Ed Knobloch

See that big black strip on the meter? Thats tune position. Run 20 to 25
watts of drive from the exciter. Try tuning the plate and load so it is
even with that mark.

If it has been sitting around a while you may have problems in the
electrolytics.

If you tuned it up with high drive, and had the cap maxed out you may indeed
have blown the grids out of a 811 or two.

If you did they will 'rattle' and you may be able to see some trash in the
tube rolling around.

Dan/W4NTI