Opek SWR-7 Meter

[Sarasota Slim]

The other day, I was in Iowa, so I stopped at Walcott Radio (not my favorite place), and picked up a new meter to replace my Astatic PDC-2.

I like it ok, though it seems to register a higher SWR than the old Astatic.

I'm curious, though; does the power on that meter do anything more than simply power the LED backlight? I like to keep my meter in line, to alert me to possible issues with my system, but there is no switch to turn the backlight off.

I'd like to put a switch in, and possibly put a colored bulb in (as it currently is, I have a big white square reflecting off of several surfaces), but I don't want to do anything to destroy the functionality of the meter.

Anybody here have a familiarity with the Opek SWR-7?

 

[midnight special]

looking at owners manual and checking the sales brochures... it seems the power lead just to the led light function,,, i would just leave it unhooked or place a switch in line to turn it off if not needed,,,

 

[fourstringburn]

That's correct, all the 12v source is for the meter lamp.

While that meter is probably better than the average cb shop meter, it doesn't have a true active peak power reading circuitry that does require 12v power.

Cross needle meters are nice once you get used to them because you see your FWD power, SWR, and any REF power all at once without any calibrating like most single meters.

Also it's best for better accuracy to apply enough RF power to show at least 50% power scale on the meter.

Having said that, are you sure you are reading the SWR correctly? The SWR is where the 2 needles intersect over the nearest SWR line markings on the meter face. This may be why the SWR seems higher compared to your Astatic meter.

Also you need to subtract any REF power from the FWD power for true power out. This is true with any meter but mist people don't do it.

 

[Sarasota Slim]

Ok, thanks guys. I figured that the light was the only thing using power; I actually cracked open the case, to see. The power wires disappeared into the meter face, so I couldn't tell, for certain.
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I am sure that I am reading the meter correctly, lol. It's kinda self explanatory. I had been wanting a cross needle meter, for a while, anyway, and needed something that read more than 100 watts, and didn't feel like waiting for the mail (also, I probably won't see my mail box for a few more weeks, lol). I happened to be near Walcott when they were open, and they had a meter that was pretty much what I wanted, that fit my immediate budget.

I figure that the somewhat higher SWR reading probably has something to do with greater accuracy than the Astatic, but I could be wrong. Also, I hadn't checked the SWR on the Astatic, lately, and I know that I have a small issue on my antenna to fix, so the Opek is probably reflecting that fact.

It did not dawn on me to subtract reflected power from forward power, though now that it's mentioned, that makes perfect sense. Thank you for the tip, FourString.

 

[Sarasota Slim]

Well, I don't reckon that I'm too impressed with Opek. As I mentioned above, the SWR seemed to read a bit higher on it. At first, it was a minor difference.

I've been making some changes to my antenna system lately, and having a devil of a time getting things adjusted right. Finally, I ended up removing everything, including the meter, from between the radio and antenna, and using the meter on the radio to "ballpark" it, with the intent of adding the external meter in to fine tune, afterwards.

I got the radio meter reading as low as 1.00 (I don't think the radio meter is very sensitive, lol), but when I hooked up the Opek meter, it was reading 8, and the radio was reading 9! So I swapped out jumpers, and got the same result. Removed the Opek meter, and the radio reading dropped back down to 1. Added my old Astatic in line. No change on the radio meter, Astatic read under 1.5.

So, it seems that I either got a defective unit, or Opeks really can't stand riding in a truck.

This is highly inconvenient. I have no idea when I'll be able to catch Walcott open, again. Even so, my wife inadvertently pitched the receipt.

Guess I'm in the market for another meter. I really like the idea of the cross needle design; I can make mental notes of SWR while driving, with those. Can't safely do that, with the Astatic.

 

[fourstringburn]

If your looking for a good mobile watt meter that has active peak reading circuitry, this is what I use. This meter is great for mobile because it is just the right size for mounting on your dash or anywhere.

You will notice it has a separate small box for your coax connections so you can mount the meter anywhere you like without having to bring the coax cable to it. You just run the supplied sensor wire from the sensor box to the meter. The sensor wire is just a Cat5e cable. Also the 12v cable is plugged into the sensor box too providing power for the active circuitry and meter lamp.

This meter comes in 2 different models, a 100w/1000w or a 300w/3000w version.

 

[Sarasota Slim]

If your looking for a good mobile watt meter that has active peak reading circuitry, this is what I use. This meter is great for mobile because it is just the right size for mounting on your dash or anywhere.

You will notice it has a separate small box for your coax connections so you can mount the meter anywhere you like without having to bring the coax cable to it. You just run the supplied sensor wire from the sensor box to the meter. The sensor wire is just a Cat5e cable. Also the 12v cable is plugged into the sensor box too providing power for the active circuitry and meter lamp.

This meter comes in 2 different models, a 100w/1000w or a 300w/3000w version.

That's pretty spiffy. Thanks for the tip.

 

[w9cll]

Well, I don't reckon that I'm too impressed with Opek.

Cheap Chinese made products, on par with Barjan and other crap sold in truck stops and other low end stores.

 

[Sarasota Slim]

Cheap Chinese made products, on par with Barjan and other crap sold in truck stops and other low end stores.

And costs 4 times as much. Outside of old stock, I'm not sure that Barjan exists anymore; they were, if I recall correctly, absorbed by another company, which was, in turn, absorbed by DAS.

As crappy as the Astatic meter is, (Astatic is another DAS company) it cost about $20, gets me in the ballpark of where I want to be (best as I can tell), and doesn't appear to harm anything, that I can discern. Which is more than I can say for the Opek meter.