[Hallicrafters] HT-32 PTT and runaway in finals

[psturdivant n1ps]

I have read of many warnings about the 6146B.  I have stayed away from that
bottle for this rig (the HT-32 Mark1).  You bring up a good point about the
SS rectifiers.  I wonder if this contributes to the problem?  Steven G. has
an interesting fix...

For certain I am going to go through the proceedure in the book on finals
neutralization.  I wonder about adding a bias resistor to cut down the plate
voltage some (thus reducing the gain a bit perhaps).
ps
----- Original Message -----
From: "Glen Zook" <gzook at yahoo.com>
To: <stevengrant98 at yahoo.com>; "psturdivant n1ps" <sturdivant at adelphia.net>;
"Hallicrafters List" <hallicrafters at mailman.qth.net>
Sent: Sunday, December 22, 2002 4:07 PM
Subject: Re: [Hallicrafters] HT-32 PTT and runaway in finals


> Use the 6146B ONLY if you can neutralize the circuit!
> The solid state rectifiers will increase the B+ by up
> to about 50 volts, but will not make any real
> difference in whether or not you should use the 6146B.
>  The voltage in both the HT-37 and the HT-32 doesn't
> go that high when you go to solid-state rectifiers.
>
> Some rigs that were manufactured for the 6146 / 6146A
> work fine with the 6146B.  Then, other rigs of the
> same exact model, even those with very similar serial
> numbers, will not work properly.  If the rig was
> designed to use the 6146B then there will not be any
> problems.  But, I have seen way too many rigs that
> were not designed to use the 6146B that have suffered
> greatly by the substitution of the 6146B for the
> earlier model tubes.
>
> I know that there are people out there who insist that
> the tubes are interchangable.  However, I know a whole
> lot more people who admit that they have had all sorts
> of problems using the 6146B.  Also, one set of 6146B
> tubes might work fine.  Then, those manufactured by
> another company or those from another "lot" from the
> same manufacturer won't work at all.
>
> As I say at the end of the 6146 article, substitute if
> you must.  However, be aware that you are treading on
> thin ice.
>
> Glen, K9STH
>
>
> --- Steven Grant W4IIV <stevengrant98 at yahoo.com>
> wrote:
>
> if you are using solid state replacements in the
> rectifiers, or are doing heavy service you must use
> the 6146B
>
> =====
> Glen, K9STH
>
> Web sites
>
> http://home.attbi.com/~k9sth
> http://home.attbi.com/~zcomco
>
> __________________________________________________
> Do you Yahoo!?
> Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
> http://mailplus.yahoo.com
> _______________________________________________
> List Administrator: Duane Fischer, W8DBF **for assistance**
> dfischer at usol.com
> ----
> Hallicrafters Collectors International: http://www.w9wze.org
> ----
> http://mailman.qth.net/mailman/listinfo/hallicrafters