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What’s that short in my PA?

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kfield
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What bait?
kfield   9/20/2013 3:42:10 PM
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Hi David - sounds horrible! Can't help but ask what bait did you use in the traps? We have a terrible mouse problem here in my house, and the little devils are smart enough to avoid even peanut butter if it's in a trap!

kfield
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Good story
kfield   8/29/2013 4:38:55 PM
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You're a regular Sherlock Ohms!

David Ashton
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re: What’s that short in my PA?
David Ashton   5/15/2011 9:56:13 AM
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Not sure what the equipment was, I have a photo of it somewhere. It was a pretty fancy PA, was controlled by the exciter which told it which channel it was on and you could manually preset the Ls and Cs in the PA tuning circuits, and it would remember the settings. I had problems with the moving contacts on the Ls, got round that by using graphite from a pencil as a conductive lubricant. @ Whatever, I sometimes have craft syndrome too, @ but the 2nd last word is different... There are other interpretations, but this is a family site, huh Brian?

zeeglen
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re: What’s that short in my PA?
zeeglen   5/15/2011 2:33:05 AM
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OK, was thinking of similar to the Heathkit SB220 with the front panel CW/SSB selector which varied the plate voltage (found the schematic online). The 3-500Z grids were DC and RF grounded, + bias was applied to the filaments and was NOT switched other than T/R. Cannot recall if this was actually class C in CW mode due to plate voltage change. Then noticed from an online photo the SB220 is 2KW and you mentioned 1KW, so hunted up the SB200 schematic and saw there was no CW/SSB select. So then I assumed you were using something else. Whatever, I sometimes have craft syndrome too, but the 2nd last word is different...

David Ashton
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re: What’s that short in my PA?
David Ashton   5/14/2011 11:52:43 PM
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Nope...mac_droz is right...it would have been a linear. This was 25 years ago so please make allowances for my CRAFT syndrome (Can't Remember A Flamin' Thing....)

zeeglen
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re: What’s that short in my PA?
zeeglen   5/13/2011 2:25:26 PM
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"...in class C... Usually they worked in FSK... On Sundays, however, I’d set the radio to SSB voice mode..." Sounds like the PA tube bias was selectable for class C or linear for SSB. Have to agree this is a great story.

mac_droz
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re: What’s that short in my PA?
mac_droz   5/13/2011 9:01:16 AM
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You can't use class C amplifier for SSB but only for CW and FSK... Only class A or AB will work. Anyway great story!

David Ashton
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re: What’s that short in my PA?
David Ashton   5/9/2011 12:23:40 AM
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As the guy in Monty Python's "And now for something completely different" would say "This post is getting silly...." So how about this Hickory, Dickory, Dock The mouse he got a shock The arc struck on The mouse was gone Hickory, Dickory, Dock

David Ashton
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re: What’s that short in my PA?
David Ashton   5/9/2011 12:05:10 AM
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I didn't mention the cats - as another poster remarked, my story was long enough already.... When I was there they had introduced a cat flu virus and we saw a fair few sickly and dead cats as a result of this. However as usual some of them were immune and bred up the population again. They also tried shooting them - we had a couple of guys on Marion doing just that - but 2 guys to cover over 100 square Km just doesn't work. When was your friend there? Ref the hens - nice story...

cdhmanning
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re: What’s that short in my PA?
cdhmanning   5/8/2011 11:59:19 PM
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My grandmother had a very soft spot for her bantam hens which would walk around anywhere they wanted - including in the house. When one nested in the back of a valve radio it was left there to hatch out its brood and nobody was allowed to turn the radio on for fear of overheating the eggs or starting a fire. Since WW2 was on at the time, the family would get on horses and ride 5 miles to the neighbour every noon for the news. When a friend of mine went to Marion, the major pastime was hunting cats. The cats, which had been release to control the mice, were instead killing off the burrowing petrels and needed to be controlled.

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