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What’s that short in my PA?

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zeeglen
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re: What’s that short in my PA?
zeeglen   5/5/2011 2:34:47 AM
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Wow! David, you have the makings of the perfect mousetrap. Patent this, and all the world's mice will beat a path to your door (or something like that). Seriously, another good story. I've pulled cockroaches from between relay contacts, but never had a mouse problem like yours. Also interesting to learn that there is more than one Prince Edward Island in the world (another is in Canada). Enjoyed the read.

David Ashton
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re: What’s that short in my PA?
David Ashton   5/5/2011 3:52:03 AM
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Thanks Glen. Back in Zim I fixed a lot of radios for the locals in my youth, and cockroaches were a major problem. So I started charging extra per cockroach (and more extra for live ones!). Then I got radios full of insect powder... We got pretty inventive on Marion with mousetraps. Good one was an empty food tin (about 18 inches high, 10 inches square, with a round lid about 8 in diameter on top. Balance a bit of old plank on top, with a tasty morsel at the end. Mouse comes along, goes to tasy morsel, overbalances plank and into the tin. Take plank and squash them (not pleasant but if you let them go they come back again...). I think there are cheaper traps than 1kw PAs....

zeeglen
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re: What’s that short in my PA?
zeeglen   5/5/2011 8:32:21 AM
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(Replying to original post to prevent text area shrinkage) Another impressive point of your story is that you froze your butt getting those antennae back up to get comm to the outside world, right when Graham needed this the most. Your's was a very important job....

David Ashton
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re: What’s that short in my PA?
David Ashton   5/5/2011 10:54:25 AM
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Glen...as an aside, I now have a Win XP PC going and it does much better on the threads and does not lose text at the edge. Still struggling with it though (NVIDIA support....grrrr) I only learned Graham was ill when I went back in to the base after getting one of the antennas back up. But I must admit I was relieved when it worked...as you say we really did need it. I said I had the best job on the base....when things were working. When they weren't - be it water feeds freezing, things needed moving, antenna blowing down or guys getting sick - everyone pitched in and helped. I had one of the other guys passing me bits and pulling for me when I was up the pole. It's teamwork - and fortunately we had a really good team, which made life easier for everyone. Graham - when he was team leader - set a really good example. He'd go down to the food store by himself and start sorting stuff. Then someone else would go down for something and start helping. eventually half the guys would be there and the job would get done in no time. I'd recommend something like this to anyone as the best way you can spend a year. You learn so much - about yourself, living with other people and all kinds of other stuff. I actually tried to go back recently but I'm now diabetic and they wouldn't take me :-(. So if you're young and healthy - just do it!

Sheetal.Pandey
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re: What’s that short in my PA?
Sheetal.Pandey   5/5/2011 10:59:13 AM
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A good story...and a very long one too. But its always good to know how people learn from their experiences an dbecome a pro in some tasks.

zeeglen
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re: What’s that short in my PA?
zeeglen   5/8/2011 1:57:23 AM
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I cannot resist making a silly post. A couple weeks ago I posted how some of the recent article titles resemble old songs. Same for this article - please bear with me and enjoy the attempt at humour. David, maybe you'll sing this the next time you hoist a pint. What's that short in my PA? What's that short in my PA? What's that short in my PA? Cried the fair young maiden. It's only a mouse that got too clouse, said Barnacle Bill the Sailor!

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

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.

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...

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!

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.

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   5/15/2011 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   5/15/2011 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?

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!

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!

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