I tried substituting a 500 foot run of telephone cable between another
manufacturer's SWR/wattmeter and its remote coupler. Works just fine, with
no loss of accuracy. I imagine the Shack unit will work fine, too.
73, Dick, WC1M
-----Original Message-----
From: Patrick.Croft. <mai@iquest.net>
To: Rolfe.Tessem. <rolfe@ldp.com>
Cc: Towertalk@contesting.com <Towertalk@contesting.com>
Subject: Re: [TowerTalk] Radio Shack remote-reading wattmeter
>Rolfe,
>
>Have you tried the meter with the 500 feet of cable attached yet? I'm
>curious of the units ability to drive that much line, as usually this type
>of situation would require line amps. One would need to retain the 10%
>accuracy of this R/S unit to be meaningful.
>
>These units were reviewed in QST a few months ago, and the R/S displays at
>the hamfests I've attended in the past year has had these on display.
>Checking with the local R/S district revels about 100 units in the area.
If
>someone wishes this unit and the local doesn't have stock, just ask them to
>transfer one from another district or Ft Worth.
>
>Let me know your success story on remoting 500 feet!
>
>Bests
>
>Patrick
>
>At 04:25 PM 8/4/97 -0400, you wrote:
>>I was unaware of this product until Jim Miller of Comtek Systems brought
>>it to my attention recently. It turns out that Radio Shack is closing
>>them out so if you are interested you may want to call your local store
>>and see if they still have one in stock. The catalog number is 21-527
>>and the price is around $50.00 I think.
>>
>>This is a digital wattmeter with remote pickup head. The connecting
>>cable is three-conductor, about number 24 wire.
>>
>>The reasons I'm bringing it to the list's attention are twofold. First,
>>I think Radio Shack did a bad job of advertising this unit -- I'd never
>>heard of it until I went into the local store and asked about it.
>>Second, if you are using a phased vertical array with Comtek's hybrid
>>coupler to accomplish the proper phase relationships, you know that you
>>need to monitor the power being dumped into the dummy load. So, you have
>>a choice of running lots of coax from the coupler unit back to the
>>shack, putting the dummy load there, and monitoring the power with a
>>conventional wattmeter. Or, you can use something like this Radio Shack
>>unit.
>>
>>In my case, the run from the shack is 500 plus feet, and the choice of
>>500 feet of RG-213 or 500 feet of cheap telephone wire was an easy one.
>>
>>The wattmeter has three ranges -- 20 watts, 200 watts, and 2000 watts --
>>as well as an autosensing position. With the touch of a button, it will
>>also read SWR directly. The control head display consists of backlit
>>LCD's about 1/2" high and the head itself is about 4" wide by 1 1/2"
>>high. It has a bracket on it that suggests that it was intended to be
>>used in mobile applications. There is also a front-panel button to
>>switch between peak and average reading. The remote head looks
>>well-sealed and relatively weather-proof, but the manual suggests
>>sealing with one of the compounds designed for that job if it's going to
>>live outdoors fulltime.
>>
>>So far, the unit works as advertised and seems to fill a missing niche.
>>
>>As always, YMMV, but to me -- especially at the closeout price -- this
>>seems like an excellent value.
>>
>>Rolfe, W1VC
>>
>>--
>>Rolfe Tessem | Lucky Duck Productions, Inc.
>>rolfe@ldp.com | 96 Morton Street
>>(212) 463-0029 | New York, NY 10014
>>
>>--
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>>
>>
>
>
>--
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