[ARC5] R1155: Getting to Work

[Bill Cromwell]

Hi Dave,

Good job working on the old radio. I have been running my command 
receivers on 90 volts B+ from a stack 9 volt batteries in series. It is 
practical and the current draw at 90 volts is around 15 mA for the six 
tubes. I tried 45 volts B+ on one BC453 and it played with that voltage 
but performance was noticeably down. B+ current was about half or around 
8 mA. Some bias changes might get the performance up at 45 volts but 
probably increase current drain. I am not interested in making mods like 
that. I don't know how many tubes the R1155 has (too lazy to look) but 
your results seem within reason.

I'll be watching the continuing story.

73,

Bill  KU8H

On 05/03/2017 01:13 AM, David Stinson wrote:
> First:  Thank you everyone for your kind help and information on the 
> R1155 resurrection.
> I continue to be grateful for our community. Awesome.
> ---snip---
> said a little prayer and applied 45 Volts to the B buss.
> The radio was on Band 3 (3-7.5 MC) and there was the
> familiar "BFO-On" noise floor, but no signals.  Found that there is a 
> disconnect between the ANT connection and the RF Amp. Connected the 
> antenna directly to C59
> (grid input coil for Band 3)  and the radio took a breath
> and played.  However, Bands 1 and 2 had no LO operation
> at 45 Volts, so popped it up to 80 Volts.  The radio came alive 
> then.   Had to crank down the signal tracer.
> https://goo.gl/photos/h8Fy7EFo56YjHMZ39
>
> B-buss current at 80V was about 15 mills.
> After playing it at 80 V. for about 20 minutes,
> slowly brought the set up to 200 V for a short test,
> while watching the current.  At 200V, it pulls about 30 mills. Did not 
> leave it there long.  Risky taking it there in the first place,
> but I just had to see that eye tube glow.
> https://goo.gl/photos/xMS937JEgfpEUFmM8
>
> There's still plenty to do.  Need to find that antenna
> connection issue.  Work over the grounds.  Test all the tubes. Refurb 
> the Type 35 dial drive.
> Determine the "right" B+ buss level for long-term operation and 
> preservation.  Complete alignment.
> And a deep cleaning.  Then to find the loop and meter (wishful thinking).
>
> We're on our way.
> GL OM ES 73 DE Dave AB5S
>
>
>
>
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-- 
bark less - wag more