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Gerowen
02-15-2014, 10:53 PM
So I have a Cobra 148 GTL with a 36" Lil' Wil' antenna in my Ford Explorer, and I have a question. It has always had higher SWR than the same setup in my Dodge pickup and the house radio (Both of those are pretty close to a 1.0 all the way from 1 to 40). The whip is seated as far down in the base as it can go.

Using the meter on the radio, I get an SWR reading on channel 1 of a 1.0, and an SWR on channel 40 of about 1.7.


Using an inline meter, a Workman SWR-2T, with a 3 foot jumper coax, I get an SWR reading on channel 1 of 1.0, and a reading on channel 40 of just above a 3. I don't spend a lot of time on higher channels, but it is a tad concerning. Would you trust the Workman meter more or the one in the radio? Could the additional 3 feet of coax from the radio to the meter be causing the increased SWR?

I tried lengthening the antenna just to check by loosening the screw and pulling the whip up about 1/8" at a time and tightening it down, then re-measuring SWR, and as expected, it went even higher as I lengthened the antenna, so I pulled it back down.

the caveman
02-16-2014, 01:01 AM
The external meters tend to be a little more trust worthy than the one built into the radio. You might need to shorten your whip just a little. Be sure if you do this to do it VERY LITTLE at a time.

222DBFL
02-16-2014, 05:04 AM
The lil wilson 36" antenna is a hard one to tune, been there done that. Something doesn't seem right thought as you are saying you get a 1.0 swr reading for channel 1 and swr reading of 3 on 40, are you recalibrating your external swr meter when you change from channel 1 to channel 40, I ask this as it is just weird to have a 1.0 on 1 and a 3.0 swr reading on 40. The radio seems to be giving a more realistic reading IMO. Not saying you don't know to operate the external meter you have, something just doesn't seem right though. I am not a fan of the small workman swr meters as I have has them in the past and not had much luck with them. I now use the radio shack swr meters, they seem to be a lot better as far as accuracy goes IMO, compared to the small workman meters. Again not saying you don't know how to use the meter, but make sure when you take your readings, you are parked at least 50-100ft away from any obstructions, turn your mic gain down all the way, and then make sure to recalibrate the meter when you change channels. The 3ft jumper should make no difference, if you think it is, try a different cable if possible. And one last thing, what is the SWR reading on channel 20? Just curios. Good luck and hope you get it sorted. Personally, I would ditch the lil wil antenna if possible, they are very narrow banded antenna and are a pain to tune. I tried 2 myself and never could get the swr readings below 1.7-1.8. JMO, spend some money on your antenna system, and in return, it will give you better rx and tx, and will be easier to tune.

Silverado 996
02-16-2014, 01:18 PM
Well said 222.. I use an Astatic swr meter. The meter on my Galaxy and the Astatic meter give me the same readings 1.0 - 1.1 I would trust my meter on the galaxy in a pinch, but I still prefer an external swr meter. JMO

Good luck

Gerowen
02-16-2014, 02:08 PM
The lil wilson 36" antenna is a hard one to tune, been there done that. Something doesn't seem right thought as you are saying you get a 1.0 swr reading for channel 1 and swr reading of 3 on 40, are you recalibrating your external swr meter when you change from channel 1 to channel 40, I ask this as it is just weird to have a 1.0 on 1 and a 3.0 swr reading on 40. The radio seems to be giving a more realistic reading IMO. Not saying you don't know to operate the external meter you have, something just doesn't seem right though. I am not a fan of the small workman swr meters as I have has them in the past and not had much luck with them. I now use the radio shack swr meters, they seem to be a lot better as far as accuracy goes IMO, compared to the small workman meters. Again not saying you don't know how to use the meter, but make sure when you take your readings, you are parked at least 50-100ft away from any obstructions, turn your mic gain down all the way, and then make sure to recalibrate the meter when you change channels. The 3ft jumper should make no difference, if you think it is, try a different cable if possible. And one last thing, what is the SWR reading on channel 20? Just curios. Good luck and hope you get it sorted. Personally, I would ditch the lil wil antenna if possible, they are very narrow banded antenna and are a pain to tune. I tried 2 myself and never could get the swr readings below 1.7-1.8. JMO, spend some money on your antenna system, and in return, it will give you better rx and tx, and will be easier to tune.

Yep, re-calibrated it every time I changed channels. Flip the switch to FWD, hold dead key, rotate calibration knob until the needle is at the "SET" mark, then flip switch down to REF. I think it's probably the meter. I checked the radio on my 4 wheeler and it gave a 3+ reading as well, and I used it for the first time when installing a radio for a friend and got a 3+ reading. I even went so far on his as to measure out 18 feet of coax to run and using a voltmeter to check for continuity and shorts when we got it all mounted, and I never could get it to go down. Next time he comes over, I'll pull one of my 148 radios out of the vehicle and use it on his antenna to check SWR and just see what it says.

the caveman
02-16-2014, 11:23 PM
Well said 222.. I use an Astatic swr meter. The meter on my Galaxy and the Astatic meter give me the same readings 1.0 - 1.1 I would trust my meter on the galaxy in a pinch, but I still prefer an external swr meter. JMO

Good luck
The meter on my galaxy sucks compared to my external meter lol

222DBFL
02-17-2014, 05:50 AM
While I agree 100%, using an external meter is the way to go, something just doesn't seem right with the readings that are being obtained by the poster. I think he has a bad meter and that is why I suggested going by the internal meter in his situation. I have had issues with the truck stop swr meters as well (the small one like the one posted about), they are hit or miss IMO, as I have seen some that the needle was way off from zero in the box, and through my own experience with them, i threw mine out and went with the radio shack meter. Have not had any issues with the radio shack meter, or any of the old ones that I had either. Anyway, to the poster, hope you get it sorted and god bless.

halfwatt959
03-02-2014, 07:11 AM
I need to get a couple of new meters myself. My old radio shack swr/watt meter suffered a catastropic overload. My fault. I was checking deadkey watts on the 10 w scale when skip came in strong, so I pushed the little button and keyed up without changeing the scale to 1000w. That 150 rms blew the diodes I think not sure but doesnt read right anymore. My workman swr/watt/field strength I wasn't paying attention and hooked up backwards. It only reads about 2w when hit with my barefoot Galaxy959 doing I know close to 33-34w. Again my fault for being stupid and getting in a hurry not paying attention to detail

mjd420nova
03-06-2014, 12:48 PM
Every piece of coax changes the overall impedance and attenuates the signal. That short three foot coax could surely change the SWR. I would more likely suspect the short piece as being party shorted or acting as a stub. That 3 is way to high. The lower reading on lower channels means the antenna is too long. Little half inch snips at a time. I use the higher freqs more so it would need to be shorter.

BOOTY MONSTER
03-12-2014, 12:01 PM
most cb shops will check your swr for free with a decent swr meter or analyzer .

mjd420nova
03-12-2014, 06:56 PM
I have one of the old type with the reversable slugs for frequency and power range. I'd sure like to find one of the original penetrators. They have a high takeoff angle good for skip and could take 1,500 watts. The next choice would be the old Antenna Specialists M 400 Starduster.

redwagon
03-12-2014, 11:11 PM
Look for a loose ground or make a better ground then test. Use a 16 gage wire and connect to coax end the metal part and find ground like seat frame that s a better ground to frame grounding. Have olms reading to that may show if there is bad cable or jumper and check you meter. continuity is that all is well with you coax. You would not need to test radio because it will show a closed circuit.

BOOTY MONSTER
03-12-2014, 11:43 PM
I'd sure like to find one of the original penetrators.

http://www.dxengineering.com/search/department/antennas/section/hf-vertical-antennas/brand/hy-gain/product-line/hy-gain-spt-500-super-penetrator-hf-vertical-antennas?autoview=SKU&N=4294953330%2B4294952719%2B402111

redwagon
03-13-2014, 12:05 AM
Sure would be nice to have access to a MFJ analyzer

Tallman
03-25-2014, 09:10 PM
The M-400 Starduster is still being made by SIRIO. H&Y electronics has them in stock. I have been running my M-400 for about five years now. I had to repair the plastic piece that holds the radial spreader around the mast, but that was only after a tornado came with in a mile of the house last spring. Other than that no problem.

mjd420nova
03-26-2014, 10:20 AM
Good to know. They really stand up to the weather even with minimal support. I've even just stood them on the three radials on a roof. Great skip shooter and easy to match. I like the upper freqs so I shortened the stick a bit to match better.