[AMRadio] Re: B&W 5100B Audio Mods


Tom Elmore tom at telmore.com
Thu Oct 21 20:27:29 EDT 2004


The unit I have has a separate B+ supply for the screens. So would this be
self-modulating then?

-Tom
----- Original Message ----- 
From: "ne1s" <ne1s at neandertech.com>
To: "Discussion of AM Radio" <amradio at mailman.qth.net>
Sent: Wednesday, October 20, 2004 8:56 AM
Subject: [AMRadio] Re: B&W 5100B Audio Mods


> i am not familiar with the 5100B, but I would be VERY surprised if the
> screens weren't modulated as well as the plates - it is absolutely
necessary
> to achieve 100% modulation of tetrode, pentode, or beam-power calss C RF
> stages. This is usually done with this class of transmitters (~100W
> commercially-manufactured ham AM rigs)with a screen droping resistor from
> the modulated plate supply. It can also be done with a dropping resistor
> from the unmodulated B+, or an audio choke from a voltage source equal to
> the desired screen voltage; in these cases, the screens self-modulate.
>
> GL,
>  -Larry/NE1S
>
> Tom Elmore writes:
>
> >     Does, anyone know of a source for audio mods for the B&W 5100B
> > transmitter. I wonder if anyone has tried to modulate the screens in
> > addition to the plate of the finals. It appears the screens use a
different
> > power supply than the plates of the finals.
> >
> > Thank You
> > Tom Elmore KA1NVZ
> > Anchorage  Alaska
> >
> > ______________________________________________________________
> > AMRadio mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/amradio
> > Help: http://mailman.qth.net/mmfaq.html
> > Post: mailto:AMRadio at mailman.qth.net
>
> ______________________________________________________________
> AMRadio mailing list
> Home: http://mailman.qth.net/mailman/listinfo/amradio
> Help: http://mailman.qth.net/mmfaq.html
> Post: mailto:AMRadio at mailman.qth.net
>




More information about the AMRadio mailing list

This page last updated 19 Oct 2017.