Turning a Valor PMM3B in to a HT antenna

Status
Not open for further replies.
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
I have the similiar version to the Valor PMM3B and a SO239 to SMA connector and put the whip into it upside down and it fits!!!!! and works good too!!!. Now to get a BNC to SMA or some kind of SMA connector and cut off the bottom of the antenna and stick'er in to the SMA so i can have a handheld antenna. i lost my RH77CA and the magmount on the antenna is rusted and the cable doesn't work good anymore so that antenna is lousy now.
Anyone else with ideas? Anyone else with rusted magmounts that killed their antennas? I hear so much on these magmount antennas but almost every mag mount i've had gets rusty and full off water after a few years. even the Rat shack magmount scanner antenna.

Now my Larsen magmount works good though i prefer real mounts these days and one hole in my car.

Eric Burris
 
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
You totally lost me there, Bro. I can't even picture what you're saying. Got pics?

Just take the whip off the magmount and put in upside down in a so239 to SMA adapter or BNC adapter.
The top of the whip will fit those adapters perfectly. I keyed some repeaters up and it worked. seems to receive well even upside down!!!!

I just replaced the coax with RG58 and drilled the hole in the mag mount bigger and soldered the cable in and used some JB Weld to seal the cable and magnet in place.
 
Last edited:

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
Ah, I think I get it now. I assume you are taking the plastic tip off of the whip before you insert it into the connector?

I remember back in the early 1980s, when we first got cellphones on the ambulances, they were pack phones with screw on ducks. Of course, firemen being the clumsy and careless slobs that they are, most of the antennae quickly broke off. It wasn't long before someone decided that an IV needle stuck into the antenna jack might work as an antenna. And it did! Pretty soon, almost every ambulance's cellphone had the rubber duck replaced by an IV needle. Can't argue with results! :lol:
 

KC0QNB

Member
Joined
Nov 4, 2007
Messages
730
Location
Gothenburg, NE
Just take the whip off the magmount and put in upside down in a so239 to SMA adapter or BNC adapter.
The top of the whip will fit those adapters perfectly. I keyed some repeaters up and it worked. seems to receive well even upside down!!!!

I just replaced the coax with RG58 and drilled the hole in the mag mount bigger and soldered the cable in and used some JB Weld to seal the cable and magnet in place.
take a picture now I can't imagine what you are talking about., I looked at the antenna. ??????? sorry dude I still can't imagine what you did.
 
Last edited:

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
I can imagine what he did, sort of. I just can't imagine the point of it. :lol:

By putting larger coax on this discrete antenna, you defeat it's purpose. And really, I don't see how one could drill into the base and re-solder the coax efficiently. It would make more sense to simply cut the stock coax down to maybe a 12 inch pigtail with a connector on it (just enough to get inside the vehicle), then connect it to heavier coax going to your radio.

And why would you want to turn the whip upside down, making it top-heavy and floppy, even if it does work?
 
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
Ah, I think I get it now. I assume you are taking the plastic tip off of the whip before you insert it into the connector?

I remember back in the early 1980s, when we first got cellphones on the ambulances, they were pack phones with screw on ducks. Of course, firemen being the clumsy and careless slobs that they are, most of the antennae quickly broke off. It wasn't long before someone decided that an IV needle stuck into the antenna jack might work as an antenna. And it did! Pretty soon, almost every ambulance's cellphone had the rubber duck replaced by an IV needle. Can't argue with results! :lol:

What plastic tip? The whip is all metal.
 
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
I can imagine what he did, sort of. I just can't imagine the point of it. :lol:

By putting larger coax on this discrete antenna, you defeat it's purpose. And really, I don't see how one could drill into the base and re-solder the coax efficiently. It would make more sense to simply cut the stock coax down to maybe a 12 inch pigtail with a connector on it (just enough to get inside the vehicle), then connect it to heavier coax going to your radio.

And why would you want to turn the whip upside down, making it top-heavy and floppy, even if it does work?
It was an experiment jeez.
So i guess it's wrong of me to redo the coax? I'll just pitch it in the trash then. i spent hours on that project, soldering, using JB Weld to glue the coax in place and painting the mount. all for nothing i guess. antenna works good but i guess it's a stupid idea.
 

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
What plastic tip? The whip is all metal.
Every version of that antenna style I have ever seen had a plastic protector over the tip of the whip.



Again, pics would be helpful for us to understand what you are talking about. I know it all makes sense to you because you are looking at it, but the description isn't making any sense to us without that visual reference.
 
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
Every version of that antenna style I have ever seen had a plastic protector over the tip of the whip.



Again, pics would be helpful for us to understand what you are talking about. I know it all makes sense to you because you are looking at it, but the description isn't making any sense to us without that visual reference.
it looks like the one on the left.

I can't take pictures because my camera is broke.

eric burris
 

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
The one on the left is the KM3. The one on the right is the Valor PMM3B. The Valor has been now replaced with the ProAM (bought Valor, I think) PMM3B, which looks more like the KM3, but still has a plastic tip on it.

I wasn't criticising your experimentation. I'm one of the biggest proponents of antenna experimentation you'll find on this forum. I -- along with KC0QNB -- were just trying to figure out exactly what you were doing. We assumed that you would want us to actually understand what you were talking about.

Your subject line says you are trying to make an HT antenna out of this thing, but then you talk about replacing the coax on it. What do you need coax for on an HT antenna? What do you even need the base for on an HT antenna? And why would you stick it in upside down instead of right side up? I'm not at all against the concept. I just would like to understand what it is you are trying to achieve.

See why it is hard for us to understand what you are talking about? We're not being critical of your experiment. If anything, we're being critical of your unclear posts, although that was not my intent either. If I didn't really care about what you were saying, I wouldn't be wasting my time responding at all.

Now, are you SURE that the tip on that antenna is not plastic? Both of them I have handled very definitely had plastic tips on them, albeit very hard plastic.
 
Last edited:
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
The one on the left is the KM3. The one on the right is the Valor PMM3B. The Valor has been now replaced with the ProAM (bought Valor, I think) PMM3B, which looks more like the KM3, but still has a plastic tip on it.

I wasn't criticising your experimentation. I'm one of the biggest proponents of antenna experimentation you'll find on this forum. I -- along with KC0QNB -- were just trying to figure out exactly what you were doing. We assumed that you would want us to actually understand what you were talking about.

Your subject line says you are trying to make an HT antenna out of this thing, but then you talk about replacing the coax on it. What do you need coax for on an HT antenna? What do you even need the base for on an HT antenna? And why would you stick it in upside down instead of right side up? I'm not at all against the concept. I just would like to understand what it is you are trying to achieve.

See why it is hard for us to understand what you are talking about? We're not being critical of your experiment. If anything, we're being critical of your unclear posts, although that was not my intent either. If I didn't really care about what you were saying, I wouldn't be wasting my time responding at all.

Now, are you SURE that the tip on that antenna is not plastic? Both of them I have handled very definitely had plastic tips on them, albeit very hard plastic.
it's metal and the paint is wore off on the edges and it's shiny and the signal is fine upside down so if it was plastic wouldn't i already know that ;) my dual band version that i think is an Opek has a metal tip as well. i was thinking of making the whip into a HT antenna if the mag mount couln't be repaired. that's 2 mounts i had to redo now. i don't hear others having rust problems with water inside them but both of mine got ruined.

eric burris
 

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
Ahh! Now that's helpful! I can only find one dealer for Opek Antennas, and that's http://www.wilcopc.com/HamRadio/opekmobant.html . I might have to order one of those and compare it side-by-side with the KS3 and the PMM3B. The price is about the same. I too am curious if others have had problems with these things failing in the weather.

And now I better understand why you are trying to replace the coax too! I guess before I use one of these for any period of time, I will use some silicone sealant around the whip.
 

stevolene

Member
Joined
May 5, 2006
Messages
173
Location
chattanooga metro
it looks like the one on the left.

I can't take pictures because my camera is broke.

eric burris
you know that picture of the pmm3 is misleading, in the picture the antenna appears to have 2 solid loads, when in fact its the same antenna as the km3, I ordered both at the same time, one from universal and one from R&L, both excactly the same. both good antenna's
 

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
They aren't solid in that pic. They are just very tightly wound coils, like a PCS cellphone antenna (which is basically where the design came from). Originally, they were like that, before ProAm took over the line from Valor. Now they look pretty much like the KS3, with the wider coils.
 

af5rn

Member
Joined
Apr 4, 2008
Messages
1,061
Location
N. Tex / S. Fla
Yeah, I'm not sure who bought who, but they are apparently one in the same now.

I liked the old look, with the tighter coils, better than the new look. I wish I could get hold of an old one though, just to test the difference.
 
Joined
Dec 24, 2004
Messages
787
Location
Emporia, KS
Yeah, I'm not sure who bought who, but they are apparently one in the same now.

I liked the old look, with the tighter coils, better than the new look. I wish I could get hold of an old one though, just to test the difference.
When did the company buy the other?

My antenna with the longer coils was bought many years ago but the catalog photo showed the tighter coils like the Valor. I thing i've got it from ham radio outlet if i remember correct. I've always wondered why mine didn't look like the photo. I think the tighter coils looks better. I notice with mine when it gets iced up it flops off the car and hangs on the side of the car on the highway. everyone talks how good the magnet is but not with ice on it.

Eric Burris kc0ldt
 
Status
Not open for further replies.
Top