I found a goldmine

[WSHH887]

I live in a port town. For my entire life I have driven past a marine electronics store. Not needing "marine" electronics (radar, sonar, gps and its predecessor LORAN, and of course radios). I never had a need to visit. But as it turns out the store carries all sorts of GMTS, FRS and HAM equipment. And not just for boats.   
 

i called yesterday and found out that not only do they have probably everything you find all your needs met in one place. Plus and more importantly, they are more than to share decades of knowledge and experience. 
 

Heading down tomorrow with a list of needfuls and more importantly a list of questions. 
 

 

[Socalgmrs]

Great. Always good to have a good local store.  I don’t really think gmrs should have many questions. It’s suck a simple service I think many/most people over complicate it to a point that loads of time effort energy and money is spent to do the same thing some guy does with a few bucks and a few minutes. 

[PRadio]

2 hours ago, Socalgmrs said:

Great. Always good to have a good local store.  I don’t really think gmrs should have many questions. It’s suck a simple service I think many/most people over complicate it to a point that loads of time effort energy and money is spent to do the same thing some guy does with a few bucks and a few minutes. 

Yep, that's why Midland is a good choice. Glad we agree.

[WRUU653]

This makes sense. Thanks for the tip. It surprises me I never considered this as my father used to commercial fish. 

[WSHH887]

Finally got down to the marine electronics store.  Quite a learning experience. They don't usually do a lot of GMRS stuff, but certainly have everything needed to install them .  they also can make up a custom coax.  

Unknown to me was that there are a number of different types, including some that are designed for high heat environments.  Stranded and non stranded.  Made a lot of recommendations on coax routing, grounding and on and on.  Frankly, it was overload, but they said to just call with any questions.  So, for my NMO mount and coax I need to get an accurate measurement and let them know and they will make it up.  Apparently, it's a high complicated five minute job.

I had figured I would get a premade coax longer than needed and just loop the extra and stuff it out of the way.  Apparently it's not a good idea to loop the cable. 

[TerriKennedy]

4 hours ago, WSHH887 said:

Finally got down to the marine electronics store.  Quite a learning experience. They don't usually do a lot of GMRS stuff, but certainly have everything needed to install them .  they also can make up a custom coax.  

Unknown to me was that there are a number of different types, including some that are designed for high heat environments.  Stranded and non stranded.  Made a lot of recommendations on coax routing, grounding and on and on.  Frankly, it was overload, but they said to just call with any questions.  So, for my NMO mount and coax I need to get an accurate measurement and let them know and they will make it up.  Apparently, it's a high complicated five minute job.

I had figured I would get a premade coax longer than needed and just loop the extra and stuff it out of the way.  Apparently it's not a good idea to loop the cable. 

I dislike NMO connectors. With just about every other type you plug the cable into the antenna, turn until the shell stops, and you're good to go. With NMO, if you're using an adapter to any other connector type, or you're mounting the NMO connector through a panel that is even slightly different from what the manufacturer expected, you have to fiddle with how far in you thread the adapter and you only get a turn or two of thread engagement, and you may or may not have a water resistant connection. Right now I'm using a temporary NMO antenna. The real antenna going up in two months will be a DB408-B with an N connector (my favorite type).

Cable loops beyond what is needed for drip loops can degrade your SWR. 50' of 400-type ultraflex (LMR400 is a trademark of Times Microwave) in a coil into a dummy load had a SWR of 1.28. Not great, not terrible (gratuitous Chernobyl reference). With the ultraflex uncoiled except for a drip coil at the base of the antenna and at the building entry, even with a real antenna instead of a dummy load, SWR dropped to 1.12. I expect the custom length of Heliax  on the DB408-B will do even better.

[WSHH887]

Depending on where and how you mount the NMO mount drip loops aren't necessary.  The folks I'm working with are a Marine Electronics shop that was started in 1960 and still run by the second generation (he's 72).  I'm pretty sure he knows all the ins and outs of antenna mounting.  I imagine most folks here would kill for this kind of resource.  

[WRTC928]

11 hours ago, WSHH887 said:

I had figured I would get a premade coax longer than needed and just loop the extra and stuff it out of the way.  Apparently it's not a good idea to loop the cable. 

@OffRoaderX (aka Notarubicon) tested this myth on his YouTube channel and found that looping the cable didn't affect the SWR at all. That prompted me to test it myself with two different pieces of coax and three different radios from 5 to 35 watts, and I also found no change at all in SWR or transmission range. I'm about to put an antenna on my truck and I plan to leave a few extra feet of coax so I change the position of the radio, plug in an HT, or whatever else may come up. I'll just coil the extra into a loop and secure it with cable ties.

[WRYZ926]

12 hours ago, WSHH887 said:

I had figured I would get a premade coax longer than needed and just loop the extra and stuff it out of the way.  Apparently it's not a good idea to loop the cable. 

That myth has been busted numerous time. It will not hurt to loop the excess coax inside your vehicle. In fact, if you have enough extra coax then looping it can help reduce noise as it can act as a common mode choke. 

Most antenna mounts come with 12-16 feet of coax with the most common being 12 feet. 

[GreggInFL]

16 hours ago, WSHH887 said:

Made a lot of recommendations on coax routing, grounding and on and on.

Lightning strikes on sailboat masts will focus one's attention.

[WSHH887]

30 minutes ago, GreggInFL said:

Lightning strikes on sailboat masts will focus one's attention.

Was on the Glomar Explorer when it took a lightning strike to the derrick. I was on the port bridge wing. You could "feel" in the air just before. Really disorienting afterwards. That's as close as I ever want to be to a strike. 

[GreggInFL]

32 minutes ago, WSHH887 said:

Was on the Glomar Explorer when it took a lightning strike to the derrick. I was on the port bridge wing. You could "feel" in the air just before. Really disorienting afterwards. That's as close as I ever want to be to a strike. 

That must have been quite the cruise.

[WSHH887]

7 hours ago, GreggInFL said:

That must have been quite the cruise.

Nope, never left the dock.  But it was one heck of a piece of maritime history.  Sadly after only three, if I recall correctly 1/2 trips to collect "magnesium nodules" it was mothballed and has now been scrapped.  

[GreggInFL]

^Those three-letter agencies love "magnesium nodules".

[Radioguy7268]

"I can neither confirm nor deny."   For the younger folks out there, check the reference to the Glomar response, and it's place in Government history.

If you really want to get wrapped up into some deep rabbit holes, check out the relationship of Howard Hughes to the whole Glomar thing.  Most kids (My college age daughter included)  have only ever heard of Howard Hughes as "The Aviator" and Leonardo DiCaprio. They don't know about Glomar, TWA, or the Mormon Will and Ice Station Zebra.

[WRUE951]

Back in the CB days my favorte radio gadget shopping place was a Marine Electronic Place in New Port Beach Ca.    The place carried everything and even had a very good selection of CB Radios.  In fact i still have a Pace 40 i bought from the place and even still use it occasionally.  That radio out of the box put out 8 watts.. I even still have some Antenna air mounts i bought there some 40 years ago..    

[WRQC299]

Nope, never left the dock.  But it was one heck of a piece of maritime history.  Sadly after only three, if I recall correctly 1/2 trips to collect "magnesium nodules" it was mothballed and has now been scrapped.  

Raise the Azorian?


Sent from my iPhone using Tapatalk

[WSHH887]

Little update.  The possible issue of looping coax isn't increased SWR.  It's noise.  Apparently depending on how and where the loops are it can be an issue.  So, if you avoid loops, you avoid problems.

By the way, someone mentioned that GMRS is so simple it should need a lot of explaining.  Well, I've been involved in firearms for over 60 years (first .22 rifle on my 10th birthday).  While I would never claim to "know it all", I do know a lot.  So, to me it's all pretty simple stuff.  But when a newbie shows up on a forum the last thing you want to do is prove how superior you are by saying things like "it's so simple even a caveman can do it" (yea, I have read that exact comment).  People don't now what they don't know.  The smart ones ask.  The smartassed one's respond with distain.  

But fear not, I shall continue to ask "stupid" questions, even when I am no longer stupid.

[WRYZ926]

On 3/16/2025 at 2:10 PM, WSHH887 said:

Little update.  The possible issue of looping coax isn't increased SWR.  It's noise.  Apparently depending on how and where the loops are it can be an issue.  So, if you avoid loops, you avoid problems.

Normally putting loops in, especially loops at certain diameter for the frequency along with certain number of turns can actually reduce noise as the loops will act like a common mode choke. 

[WRYZ926]

Here is a good read on common mode chokes. The article talks about 2m VHF but the principal works for HF bands and UHF bands too.

https://w6nbc.com/articles/2020-TBDcoaxchokebalun.pdf