[ARC5] Using WSJT-X with R-23 or BC-453B

[Scott Robinson]

Well, the RF gain changes the grid bias on the front end stages, 
changing the B+  a little, so no surprise here.

Now, about 6K8 and 6J8 converter tubes: these were invented to fix the 
horrible AVC pulling that 6A8s do. In one 1939 radio (GE-G-106, for 
those interested in wood radios) at 18 MHz the AVC would pull the 6A8 LO 
by 20 KHz, and substituting a 6K8 reduced that to 1 KHz. The radio has 
an RF amp, so the converter noise is of less significance.

Peace,

Scott Robinson


On 11/2/17 3:47 PM, J Mcvey via ARC5 wrote:
> Just noticed that the gain control also affects the BFO pitch slightly. 
> AAARRGH!
> 
> 
> On Thursday, November 2, 2017, 4:57:30 PM EDT, J Mcvey via ARC5 
> <arc5 at mailman.qth.net> wrote:
> 
> 
> I'm running it on a 24V DC supply and dynamotor..
> However , it's NOT regulated ( it's n old PBX supply.)
> 
> Since these are heaters with cathodes, why is it so sensitive?
> The BFO osc is a triode (12SR7), so no screen.
> Of coarse,  the 12K8 is another story.
> I ran both these radios on a HP 8935 for about an hour and it did seem 
> stable AM tuning wise.
> I measured the P-P output on a scope to see if there was any change. 
> however I could hear changes while using the BFO. maybe my methods were 
> ineffective...
> What do you use as a regulator? Zener? cold cathode type?
> 
> 
> On Thursday, November 2, 2017, 12:16:07 PM EDT, Kenneth G. Gordon 
> <kgordon2006 at frontier.com> wrote:
> 
> 
> On 2 Nov 2017 at 13:57, J Mcvey via ARC5 wrote:
> 
>  > I have an old military signal generator that once warmed up, is quite 
> stable, so
>  > stability can be achieved.
>  > I wish I knew how to do it with the ARC BFOs!
>  > Any suggestions?
> 
> The BFO is not the single most important cause of drift.
> 
> For one thing, you should use regulated DC for the filaments. At least 
> one other user of the
> ARC-5 gear on the MF band found that doing so enhanced stability very 
> noticeably.
> 
> And Dennis' suggestions should be followed also.
> 
> Ken W7EKB
> 
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
> 
> 
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net <mailto:ARC5 at mailman.qth.net>
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net <mailto:ARC5 at mailman.qth.net>
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> 
> 
> ______________________________________________________________
> ARC5 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/arc5
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:ARC5 at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>