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Problem attaching Mini UHF to Coax
Posted: Sat May 03, 2003 8:20 am
by F1118
I had some problems attaching the Mini UHF connector to the coax on my spectra. I than used a solder PL-259 on the coax and a adapter to convert it to mini uhf. Im not getting anything on my radio with that adapter on it. when I take off the adapter and plug the pl259 into another radio it works fine....I suppose im going to try just using the mini uhf connector now...its a crimp style . . . any tips ??? I ordered a stripping tool for rg58 cable so that maybe I could strip the coax without cutting the woven wire inside.
Posted: Sat May 03, 2003 8:29 am
by Monty
HI:
You have a few choices:
Buy a Factory Made Pigtail
Make up a new one
Or I sell " Premium" made adaptors for the
UHF Mini Series to fit just about any cable
and I use all US made connectors
Sometimes it can be a hassle to install the UHF Mini Plug
on the end of the cable , HOWEVER, if you follow the cutting
chart EXACTLY, you should be able to make it work. Just make
sure there are no shorts, and a DC Multi-Meter can be usefull
for that test
Monty
Posted: Sat May 03, 2003 8:32 am
by nmfire10
What problem are you having attaching the coax?
Posted: Sat May 03, 2003 8:55 am
by F1118
well i dont know what the problem is....i know theres a problem when my radio doesn't work though...lol
Re: Problem attaching Mini UHF to Coax
Posted: Sat May 03, 2003 9:54 am
by nmfire10
F1118 wrote:I had some problems attaching the Mini UHF connector to the coax on my spectra
What is the problem?
Posted: Sat May 03, 2003 10:02 am
by F1118
the problem is in not getting a good connection with the mini uhf alone and with a pl259 on a mini uhf adapter im not getting anything at all on my radio....the adapter was brand new from radio shack but it doesn't seem to be working...i know i have the pl259 soldered on the coax ok because when i plug it into my 2 meter radio the antenna works just fine. I think I'll have my problem solved when I get the pigtail like monty said. I've got lots of mini uhf connectors but I can't get a good connection and every time i try my coax gets shorter and shorter.lol
Posted: Sat May 03, 2003 1:07 pm
by EKLB
Radio shacks mini uhf adaptors have had a high failure rate from the package .
Id take a Ohm meter and ohm the center pin of the mini uhf adaptor to the outer housing and make sure you have a 0 ohm reading.
If you get a reading its junk=welcome to radio shack specials.
EKLB
Posted: Sun May 04, 2003 9:44 am
by Alan
Id take a Ohm meter and ohm the center pin of the mini uhf adaptor to the outer housing and make sure you have a 0 ohm reading.
0 Ohms = short circuit?
You would prefer to see a high resistance (>10 meg ohm)
Posted: Sun May 04, 2003 11:14 am
by 60hzEE
Hmmm. Probably just semantics.
The problem is most likely a damaged miniUHF socket in the radio. One of the reasons, that Monty sent you a picture of the pigtail adaptor.
/\/\ doesn't do a very good job with strain relief on the mini socket. The nut on the outside of the PA housing ISN'T backed up on the inside. So, if you appy upward, downward or sideways force via an RS adaptor, you can break the mini socket loose from the PA pc board. Also, the minisocket barrel can separate, if someone tightened the stop nut on the outside too tight. I had a Maxtrac that had intermittent output and goofy SWR. I eventually found it, and thank God, didn't blow the PA.
Use a cable adaptor, like Monty's offering, and avoid headaches.
Lee
Posted: Sun May 04, 2003 11:28 am
by F1118
I think my problem is more my lack of proper cable stripping tools rather than a damanged mini uhf socket in my radio because when I use the mini uhf alone it get a little bit of reception on the radio but when i use the adapter with a pl259 soldered on the end of the coax I get nothing at all. Just my thoughts...you could very well be right. Im not expert
Posted: Sun May 04, 2003 11:29 am
by Code3Response
Maybe some sort of tutorial could help him - does anyone know of a site for step by step crimping techniques for PL259/miniuhf stuff? Or maybe someone could give a step by step?
Posted: Sun May 04, 2003 11:34 am
by F1118
that would be nice code3.....anyway . . .im going to buy a pigtail so hopefully that fixes my problem...I probably should buy an rg58 stripper and practice on the mini uhfs before my coax becomes shorter than the length of my arm.
Posted: Sun May 04, 2003 11:38 am
by Code3Response
Thought it might be helpful - Ill look around for one, but Im sure someone out there knows of one, or maybe monty could write one!
Posted: Sun May 04, 2003 11:59 am
by Nand
Posted: Sun May 04, 2003 12:13 pm
by Alan
I'm sure I will get several resonses to this one indicating a different preference, but here it goes.
We have seen a lot of faulty installations of the MPL connectors and it is generally the 4-piece connector (seperate pin).
We have always used the same type connector that Motorola supplies with their antenna kits. It is an AMP 226600-1. It is a 3-piece connector. We install hundreds of these with zero failure rate. I personally do not use a stripping tool, but rather a good sharp Olfa knife.
Details can be found at
http://www.amp.com Select search and enter 226600-1.
We do have the proper crimp tool as the center pin can not be crimped with a standard crimp tool. It can be soldered though.
The AMP crimp tool has been dis-continued. There is a replacement, but I have yet to buy one.
http://ecommas.tycoelectronics.com/comm ... 6600_L.pdf
Posted: Sun May 04, 2003 2:03 pm
by 60hzEE
Anthony: It still sounds to me like a mini UHF jack problem on the radio. That would explain the 'no signal' through the RS adaptor. Enough strain to break the feeble path. And, would explain why you get a tiny bit of signal with just the mini connector, without proper crimping.
TYCO AMP seems a bit overdone here...... Well I have used AMP, but also use Cambridge Products MINIUHF-1, available from Mouser for $1.31 each. It's a 3 piece connector, with the center pin being crimpable, just like the BNC center pin, with a standard hex die used on BNC center pins.
When crimped, it slips through the teflon, so there's no need to solder the open end, like the AMP connector. The rest of the assembly, sleeve, threaded ring is the same. Nice looking gold contact pin too and no solder slop over or flux to clean up.
Some of the AMP center pins require a very short hex die, and I learned that the hard way.....a broken center pin (and a piece of silver plated scrap).
Good luck. You are now a graduate of MINI-UHF-101-lab. 3 units.
Posted: Sun May 04, 2003 7:46 pm
by techie
I picked up a few of the /\/\ pigtail adaptors for my truck, but
ended up not using them because the SO239 did not have a deep enough hole to accomodate the center pin on my comet diplexer.
IIRC, the fit was marginal with a genuine amphenol bnc-pl259 adaptor.
Posted: Mon May 05, 2003 5:35 am
by chad
If your using a dc grounded antenna like the maxrad mhbdc-5800 it will show continuity from the center pin to the outer shell.
Posted: Mon May 05, 2003 6:10 am
by kcbooboo
Not to steal income from another BB user, but there is someone on eBay who sells genuine Motorola pigtails for $9.99 each. I bought 10. So far they've all been excellent quality. Mini-UHF male to standard UHF female using some form of RG-58 size coax.
Having changed a DC power connector and mini-UHF jack on a MaxTrac, I can tell you that there is indeed something behind the heatsink on the UHF jack. If the nut is tight, it would take an awful lot of force to break the connector loose. I will admit that the soldered center connection does not contribute much strength. But the connector is very easily removed. The real PITA is the DC power connector leads. They are a tight fit into the plated-through holes in the PA board, and my replacement surgery ended up with the plating sticking to the power leads, not remaining on the PC board. That required me to drill some small holes through the board to connect the two foil layers before putting everything back together again. Not a fun experience.
Bob M.