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[TowerTalk] Needed, quality watt meter

To: Tower Talk <towertalk@contesting.com>
Subject: [TowerTalk] Needed, quality watt meter
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
Date: Tue, 10 Aug 2010 22:01:46 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Again, I find I have a question that probably goes best both on amps as 
well as tower talk and I do not cross post.

A while back my Bird 43 Thruline Wattmeter was destroyed, or at best, 
"over cooked" by the Muffler shroud on my large lawnmower. (It's a long 
story)
The thing got so hot it actually blew the end out of one of the slugs 
and the glass in the meter is cracked along with a very smoky housing. 
Repair would likely be more than what a new one would cost, plus slugs.

At any rate, I need to replace the watt meter and come up with a valid 
quote for the 43 and slugs.  This actually brings up two questions. 
Where is the best place to get the purchase price on  a model 43 AND 
slugs. Remember that even IF they pay for all of the "old meter and 
slugs" it's certainly not going to pay the "long dollar" so I need to 
shop as if I were the one purchasing as I really am.

The second question is what is the "best" meter in the portable class 
that does not cost as much as a piece of laboratory test equipment.
I'm currently using a Daiwa CN-801 between the amp and the Palstar AT5K 
tuner.  The 801 which is 2KW full scale goes right up against the pin at 
full carrier into a Palstar DL5K dummy load. The AT5K internal watt 
meter shows 2KW, which is what it should show IF the amp is running as 
it should when going up to "tilt". So I know the 801 is at the least, 
generous. However I have no way of checking it against the internal watt 
meter of the AT5K in the PEP mode.  I never had a chance to compare 
either of the two against the Bird 43.  I'm well aware of many of the 
problems getting an accurate reading which is why I'm working into a 
"dry" dummy load with two honkin big resistors and TWO fans that sound 
like I need to tie the desk down when they kick into high.

This leaves me with two problems. One is the requirment for a meter that 
will hit 2500 or 3000 watts full scale for the dummy load. Running this 
much full scale means that when running the legal limit which I desire 
to maintain in PEP, I will only be half scale with all the inaccuracies 
that adds in. I would *like* to come up with something that will be good 
enough to use as a reference for the meters in current use at least into 
the dummy load.  The CN-801 is generous enough that when it shows 1500 
PEP I'm likely to be some where around 1 KW PEP. Yes, I realize the 
difference between 1 and 1.5KW is not very large db wise.

Any suggestions?

73

Roger (K8RI)
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