HW-100 - 12 volt filament mod for 6883 finals
 

Will putting the filaments in parallel to run 6883 finals screw up the
filament string balance and effect the other tubes in the rig?

tnx 73 gary W4AF

I do not know the HW100, but for the HW101 I have using 6883s should be =
no problem. If you put on paper the filament circuit you will easily =
realize that putting the final tubes in parallel instead than in series =
makes no change for the other tubes.

73

Tony, I0JX

ha scritto nel messaggio =
oups.com...
Will putting the filaments in parallel to run 6883 finals screw up the
filament string balance and effect the other tubes in the rig?
=20
tnx 73 gary W4AF

wrote:
Will putting the filaments in parallel to run 6883 finals screw up
the filament string balance and effect the other tubes in
the rig?

I have the schematic of the HW-101, which succeeded the HW-100 but is
basically the same. The 6146 heaters are in series, so with a little
rewiring, 6883s can be used.

But be sure to mark the rig to show that this mod has been done,
because if at some future time someone puts 6146s in, they'll be
toasted.

73 de Jim, N2EY

On Sat, 12 Feb 2005 12:54:20 -0500, Ken Scharf
wrote:

wrote:
Will putting the filaments in parallel to run 6883 finals screw up the
filament string balance and effect the other tubes in the rig?

tnx 73 gary W4AF

As 6146's became expensive hams started using 6883's which were cheaper
but now the 6883's cost as much as the 6146's. If you are not using
the rig mobile and can fit a 1:2 or 1:4 step up transformer under
the chassis you can also find 6159's a little cheaper. These are
the same as 6146's but with 25 volt heaters. The 6159 was mostly
used in aircraft radios and is available military surplus.

G3TQD modified his HW100 so we could operate RSGB national field day
within the rules, and put a PL36 into the PA instead of 2x 6146B's.
Operated the whole contest with at least 120W input with no problems,
so I would believe it is many alternatives which are not exact
equivalents but will work fine

73 Jan-Martin, LA8AK (ex-G5BFV)
---
J. M. Noeding, LA8AK, N-4623 Kristiansand
http://home.online.no/~la8ak/c.htm