Should I adjust SWR with my little radio or big radio?

[The Tech]

I didn't want to hi-jack Bigbubbas post under the Radioactive Radios section. But he brought up a light-bulb over my head...

Hrmmm...okay I know my Stryker 440 is nothing near as powerful as BigBubbas connex 4600....

But would me trying to adjust my SWR with my Stryker be a problem? I think (based on my meter) my Stryker is deadkeying about 15 watts or so and swinging up around 60 or 65. My dumb-butt tried adjusting my antenna with my output power cranked wide open and with my mic gain cranked wide open on my Stryker. Is that why my little wil receives worse than it did when I started?

I still have my virgin cobra29ltd classic. Should I hook it back up just to set my swr? And of course turn it's "Dynamike" all the way down?

Then when my Stryker is put back in place, with it's power all the way up and the mic gain all the way up, is it just going to "look like" the SWR is bad, even if I set the SWR and get it low with my stock cobra29?

[Phaze91460]

There used to be a great comparison that SmallTruckBigRadio had on several radios on the same vehicle, mount, coax, antenna showing the different SWR reading with different powered radios.

Basicaly you want to have a very low power radio to set the SWR. The Cobra would be ideal. But you could still set um with the Striker on low power.

A radio with a built in linear like the 95T or the 4600 adds too much into the system to do a good SWR not to mention damage to the radio.

[BigBubbaBD]

There used to be a great comparison that SmallTruckBigRadio had on several radios on the same vehicle, mount, coax, antenna showing the different SWR reading with different powered radios.

Basicaly you want to have a very low power radio to set the SWR. The Cobra would be ideal. But you could still set um with the Striker on low power.

A radio with a built in linear like the 95T or the 4600 adds too much into the system to do a good SWR not to mention damage to the radio.

How would it damage the radio? Trying to fix it and reading it unaccurately?

[The Tech]

So once I hook the Cobra up and figure out how to get my SWR down (after I get my replacement whip in a few days, haha), let's say I can get it around 1.25 (I know i'm probably dreaming). Or even 1.5, and that's with the cobra29. Then I hook the stryker up and run it full power with full mic-gain, the SWR is probably going to read on the meter pretty high (like 2.5 to 3). Is this correct? And if i'm understanding this correct, is this still safe for the Stryker?

[Phaze91460]

SWR is a match between your coax and your antenna. Your radio will show differenty between different models but SWR is the same in reality.

BigBubbaBD, high SWR and keying down on your radio can blow a pill.

[Mr RadioActive]

I wrote this in another section but will retype it alittle. My my example was if your tuning a antenna like a pred 10K out of the box the SWR are is going to be HORRIBLE! If you can avoid having a 200 watt radio as the load that would be a great thing.
SWR is a ratio of how many watts are coming back. Kinda like when you flush a toilet you want 100% of the stuff going down. However on a bad toilet some comes back up. This is like a mismatched antenna. If you can make the radio watts low tuning a very poorly matched antenna your better off. High SWR can damage radios, so if your mismatched and doing 200 watts, its alot faster to blow up your radio then a 4 watt cobra.
You guys just fine tuning a antenna, or something like it YOUR FINE! Just tune your antenna as needed!

[jessejamesdallas]

Best thing to do, would be to either borrow or buy yourself a MFJ antenna anylizer. This just hooks-up from your antenna coax, to the antenna itself... Get your swr set useing this meter, and then the radio your useing wont mater. Because you set the swr with the anylizer, and not a radio.

Once set this way, any radio you use, will have the same swr...

[BigBubbaBD]

Best thing to do, would be to either borrow or buy yourself a MFJ antenna anylizer. This just hooks-up from your antenna coax, to the antenna itself... Get your swr set useing this meter, and then the radio your useing wont mater. Because you set the swr with the anylizer, and not a radio.

Once set this way, any radio you use, will have the same swr...

Do you know a part number or a link the the proper one that would work for my radio and his? guess thats 10-11 meter

[jessejamesdallas]

MFJ 259B is what you would want. It works with all bands. And can be used for other things too.
PM me for info

[BigBubbaBD]

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What about that one off there site says 10-160 meter
BAND A: 1.75 - 3.00 MHz
BAND B: 3.00 - 5.00 MHz
BAND C: 6.50 - 11.70 MHz
BAND D: 11.65 - 20.00 MHz
BAND E: 18.00 - 30.00 MHz

[jessejamesdallas]

From what it says, it may work as well. Although I have never used that one, so cant say for sure.

Now, the 259B will also tell ya how well your antenna set up is, in percentage's...Like according to my mfj, my set-up is 99% perfect match.

At one time I had it set to 100% Match, but 99% is realy about the best your going to see. This means, that the location where you were doing your tuneing, and the antenna was as accurate as humanly possible.

So IF you manage to get the antenna tuned so you see a 100% Match. If you move to a different location, next time you check, it may drop back down to 99% Match, because the location is less than perfect.

[mudder]

I agree. :06-19bik:

[BigBubbaBD]

I see what your saying.
But 300bux is high IMO. and I do not know anyone that owns one.

[Mr RadioActive]

I have a 269 in the box on the shelf at all times, not bad.
But really its untrue that alls you need to do is set your antenna with a SWR meter and its all done.
Plently of times with high watts a antenna will act differently. Example, I had a I-10K 1.1 over 60 chns. But as soon as I added a amp, swrs went up like crazy. MFJ analyzer said it was 100% Well under load the antenna malfunctioned. You couldnt see a issue until the antenna was under a bigger load.
Ive said it a zillion times, a antenna can be 100% tuned for a low watt radio. However sometimes SWRs go up, when your load is alot bigger. Under full load the antenna/mount/coax is having a issue.
I had a customer in AZ, perfect antenna 1.1 However with a 2x8 davemade swrs went crazy. His shields on his coax were not PROPERLY soldered!
In a perfect world SWR wont change no matter what radio you use. The key is however when they do, your system has a issue, someplace.

[jessejamesdallas]

I have a 269 in the box on the shelf at all times, not bad.
But really its untrue that alls you need to do is set your antenna with a SWR meter and its all done.
Plently of times with high watts a antenna will act differently. Example, I had a I-10K 1.1 over 60 chns. But as soon as I added a amp, swrs went up like crazy. MFJ analyzer said it was 100% Well under load the antenna malfunctioned. You couldnt see a issue until the antenna was under a bigger load.
Ive said it a zillion times, a antenna can be 100% tuned for a low watt radio. However sometimes SWRs go up, when your load is alot bigger. Under full load the antenna/mount/coax is having a issue.
I had a customer in AZ, perfect antenna 1.1 However with a 2x8 davemade swrs went crazy. His shields on his coax were not PROPERLY soldered!
In a perfect world SWR wont change no matter what radio you use. The key is however when they do, your system has a issue, someplace.

OK...This is true too. And likely suspects generaly are either the coax (like you said) or maybe the amp not being properly tuned. (Texas Star Amps are bad about this)

However. Once you have set the swr, by useing the mfj anaylizer, then you know that the antenna part is done. So if when you plug-in the box, if there is still a problem. At least you know it's not going to be in the antenna.

So first I would check all the conections, and coax run's, then if problem still exsists, check the amp. Or have it checked out.

As for $300 for a mfj 259B...Thats too high. Check out Ebay. I seen them listed yesterday from as little as $90. to $230. ($230 one came with a car charger adapter, which is a good idea, sence the meter use's 10 AA batterie's!) :shocked:

Seen some used ones on Ebay, under $200...

Average New Price on one is around $245, But I have seen some sites trying to sell the same meter for over $275

[BigBubbaBD]

Well my SWR is good on the 4watt cobra.. great across the board.
But as soon as it gets power the swr goes way up.. way up

Radioactive pointed out that my coax looked a little old and its getting old.
So Im thinking it is ok for a 4watt radio but as soon as I hooked up the connex it showed its age.

[jessejamesdallas]

Well my SWR is good on the 4watt cobra.. great across the board.
But as soon as it gets power the swr goes way up.. way up

Radioactive pointed out that my coax looked a little old and its getting old.
So Im thinking it is ok for a 4watt radio but as soon as I hooked up the connex it showed its age.

Could be coax. Or a bad conector. One things for sure thou. The more power you start running, the more you have to be sure everythings in perfect working order. All your duck's have to be in a row!

When amplifing your watt's, you also amplify anything that may not be set right. So a small problem @ 4w's, may turn into a larger problem @ 200w's...and @ 1000 to 2000w's, could turn into a major Melt-Down of a expencive box!....10ohm smoke, is bad new's! :8_ranting2:

[Mr RadioActive]

ahhhh a refreshing exactly!

[The Tech]

Okay, got the new stinger in for my little wil the other day. I actually got to install it today. The absolute best I can seem to get my SWR meter to read is about 1.2 on Channel 20, and about 1.75 on Channels 1 and 40. Does this make any sense? If I move the antenna up or down any, channels 1 and 40 get off-balance. But why the dip in the middle of the band? Is there any way I can get it to lower in the middle of the band without affecting channels 1 and 40?

Either way, the little wil is talking again. One guy about 5 or 6 miles from here described my radio check as, "OH YEAH! You're blowin' some major smoke out my way!" And on my way back from Wal-Mart tonight (pickin' up some groceries), somebody kept trying to key over me, and I was told, "They keep tryin, but you're walkin' all over 'em!" So I guess that's a plus.

I'm about afraid to mess with it anymore. But do you think I should? Also, keep in mind, this SWR reading is with my Stryker at full output power now with my mic gain completely down.

[BigBubbaBD]

not bad.

Wish I could say the same for mine

[The Tech]

Well I'm sure if I tried pushing 200watts through my setup, it would melt.

[BigBubbaBD]

Well I'm sure if I tried pushing 200watts through my setup, it would melt.

I havent even talked on the radio yet except for 1 radio check at low power.
I sure hope the new coax Mike said he was sending me fixes it. Im really out of ideas

[jessejamesdallas]

Okay, got the new stinger in for my little wil the other day. I actually got to install it today. The absolute best I can seem to get my SWR meter to read is about 1.2 on Channel 20, and about 1.75 on Channels 1 and 40. Does this make any sense? If I move the antenna up or down any, channels 1 and 40 get off-balance. But why the dip in the middle of the band? Is there any way I can get it to lower in the middle of the band without affecting channels 1 and 40?

Either way, the little wil is talking again. One guy about 5 or 6 miles from here described my radio check as, "OH YEAH! You're blowin' some major smoke out my way!" And on my way back from Wal-Mart tonight (pickin' up some groceries), somebody kept trying to key over me, and I was told, "They keep tryin, but you're walkin' all over 'em!" So I guess that's a plus.

I'm about afraid to mess with it anymore. But do you think I should? Also, keep in mind, this SWR reading is with my Stryker at full output power now with my mic gain completely down.

That maybe the best your going to see, with a Little Wilson.

One thing you can also try, is to move the antenna to a different location on the roof. Like if it's near the back of the roof, move to center, or Vice-a-versa...This changes your ground plane, and would require you to re-set the swr again. Any time you change the location of the antenna, you need to check swr anyway.

Like haveing my antenna in the middle of the roof, on my Suburban, best I could get swr was around 1.3 to 1.5.....but near the back, got it down to 1.0- 1.1....