Power meter reccomendation

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Roof mounted antennas for uhf /vhf and hf show no ouput with mfj 802b field strength meter. I'd like to acquire a power meter that can connect to the coax connector going to the antenna right at the antenna. Any recommendations? Thanks
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James Madden

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Posted 2 years ago

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Chris Tate - N6WM, Elmer

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in this case you will probably need to seal the couplers up in some kind of weather tight box, - and - run ethernet down the coax to the shack. but if you do..

Expensive--LP100A with UHF/VHF  coupler
Value--Elecraft W2 wattmeter with UHF/VHF coupler
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David Warnberg

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Chris, I dont think the LP-100A has a UHF\VHF coupler, I could be wrong but I have one and went the Elecraft W2 for UHF\VHF power meter route.  
LP-100A coupler

Couplers:

Standard coupler is LPC1, 3KW PEP/CW**, 1.8 to 54 MHz. 

Optional couplers for ham use include...

LPC2 0.10W to 5KW CCS*, 1.8 to 30 MHz
LPC4 0.10W to 5KW PEP/CW**, 1.8 to 54 MHz
LPC5 0.20W to 10KW PEP/CW**, 1.8 to 30 MHz

* CCS refers to continuous duty (key down). 
** PEP/CW refers to 50% duty cycle typical of most ham modes.

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Chris Tate - N6WM, Elmer

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good call.
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James Madden

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Isn't there a portable power meter with a display of some king that can be attached to the coax right at the antenna? Thanks. Jim
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George Molnar, KF2T, Elmer

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Many power meters out there - easy search at your favorite ham radio dealer's web site.
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James Madden

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Most of the meters I see are meant for the ham shack. I'm looking for somethingportable that can be used at the end of the coax where the antenna is connected. Jim
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Roy Laufer

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I have communicated with Larry Phipps, the designer and seller of the LP-100A. The nature of its design makes sampling higher than HF frequencies impossible.

This is not the case for his new LP-500/700 series. There has been a waiting list for this product, which was first announced more than 4 years ago. I started out as number #447, and finally got my own in mid December, but looking at the list, there are more than 800 anxious Hams that are still presently on it.

Larry is working very hard to fulfill his backorder waiting list. Planned accessories include both VHF and UHF couplers capable of all the measurements and displays that users now have on thre HF bands.

I don't know when the VHF/UHF couplers will be released, but Larry has assured me that they are going to be sold for the LP-500/700

(I have no financial interest in this, whatsoever - I'm just an enthusiastic customer.).

73,
Roy AC2GS
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Chris Tate - N6WM, Elmer

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well that narrows my recommendation down to the Elecraft W2..  its ok I have 4 of them.
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James Madden

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Thank you all so much. Jim
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James Madden

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The w2 looks to be a ham shack item. I'm looking for a portable handheld unit I can connect to the opposite end of a cable followed by a load to measure the output that is going into the antenna. Jim
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Chris Tate - N6WM, Elmer

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It kind of is, but its sensor based so you can put it (the sensor) up at the antenna.  I cant think offhand any other way to do it..   
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Roy Laufer

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The only thing that an SWR/Wattmeter placed closer to the antenna feed will tell you is a continuity problem between your transmitter and your coupler, but this will show in an impedance mismatch on any decent SWR/Wattmeter connected to one in the shack?
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Roy Laufer

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It sounds like you are describing a Bird 43 Wattmater, albeit it is not a remote device.

I can't imagine a situation where an run of the mill SWR/Wattmeter wouldn't suffice - if it showed the expected power output from the transmitter and negligible reflected power nor impedance mismatch, where would the RF have gone??

An unknown resistive/shielded dummy load???

Perhaps I am missing something???
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Mike - VE3CKO, Elmer

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Setup up a skype from your shack to your cell phone with your shack skype pointing to your shack meter. It's portable, safe and no cost if you have a smart phone that can handle skype, you would not want to bring a laptop with you on the roof. I have 3 Daiwa meters stacked, a CN-801HP3 for HF, CN-801HP for VHF and CN-801V for UHF though the CN801V can be used on VHF as well.
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