buying a good used GMRS repeater for neighborhood watch

[Logan5]

I am in charge of an HOA project to equip and operate a GMRS repeater in my neighborhood. I am in need of a 10 to 25 watt repeater that will suit our basic needs, but that also has scaleability and upgradeability. I am a Ham operator "General class" and also have a GMRS lic also. how can this be done cheaply? can two radios be linked? what are the options? I have "Google" searched "how to build a GMRS repeater" and not sure where to go next. Any help will be greatly appreatied, Thanks in advance.  Logan...

 

[JohnE]

look on e-bay for gr300 repeater. there should be a few out thee since they are not narrowbandable. or get a pair of M120's gm300's or alike  and youcan make a 2 wire cable to make them a repeater w/o hang time.

as for scaleability and upgrading I really don't know what more you can do except for more power or better antenna.

talk to Rich about linking machines it can bedone w/o too much effort.

hope this point you in the right direction

John

[PastorGary]

There seems to be many Kenwood TKR-820 repeaters available now that narrowbanding of Part 90 equipment is mandatory.  The TKR-820 is a tried and true workhorse and a quick GOOGLE search showed several pages of these units for sale.   The synthisizer chip must be programmed using a Kenwood  KPT20 or KPT50 interface box - which are scarce, but are still around if you look for them.

 

A single antenna and properly tuned duplexer will probably get you what you need for the group's communications. Please refer to  Part 95.179b2  for Association requirements.

[JohnE]

I completly forgot about the 820. I haven't seen one of those in yrs.

[Logan5]

ok, I obtained a Uniden SRU450KT           from an ebay seller. should arrive wensday April 3rd or later. the seller says it is set to 462.600/467.600 PL-XXXX he says it is ready for deployment. 25 watt's and includes the duplexer. I have a 30 foot pole and a Workman UVS200 so I expect it to hook right up. is there anyone who knows how to program one of these? I will need to set the time and my call letters. he also said the internal speaker was nonfunctional. I am good with electronics so i should be able to fix easily. it has an external MIC plug, but does not come with a MIC, any recomendations for a good MIC for this radio? Thank you in advance. Logan...

[PastorGary]

You don't need to have a repeater transmit a callsign automatically. In fact, since persons OTHER than your family will be using it and they have their OWN licenses, it is THEIR responsibility to properly announce ID when they are finished with their traffic. If your own ID is transmitted and someone else is doing things that they shouldn't be doing on the system, it is YOU that will have to answer to that.  With that in mind, it's probably not necessary to find programming software and a cable IF what you were told is true. Can't help you with the mic situation, but we have many members here and I hope sometone can help with that question.  I took the liberty of eliminating the CTCSS code from your post for security reasons - mainly to keep bootleggers off, because this forum is open to spybots.

 

Best of luck with the system.

 

P-G

 

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[Logan5]

Thank You. Yes he seems reputable, he has 100% feedback and he responded to my pre auction questions but I find out now that he will not ship till Monday, he is chargeing 50 bucks shipping I expected "Express" for that price.  Yes very excited to hook it up.

[Logan5]

BTW how will I set the time on this unit? or is that not one of it's functions?

[JohnE]

make sure you put a meter on that antenna from what I just read they seem to have a history of high SWR on 440 ham bands. I don't know if that will hold true on 460 though.

just somthing to keep in mind

http://www.eham.net/reviews/detail/3378

as a general rule I don't like to exceed 5% of forward power, I prefer to see less that one.

[PastorGary]

BTW how will I set the time on this unit? or is that not one of it's functions?

Don't worry about time stamp unless the repeater is connected to a computer to log usage... and it didn't sound like that's what you will be doing. I have operated on a dozen GMRS repeaters over the years and none of them had internal ID or a time stamp. As I mentioned, it is the responsibility of each USER to properly ID themselves at the end of their traffic sessions. If it is set up OK from the seller, all you need is some high quality low loss UHF cable (Andrew Hardline is what many use as well as short runs of RG213)... and some way to fine tune the duplexer, and it should be good to go.  You have a ham callsign, so check with your colleagues on 440 to see if someone is up to speed on that particular system. They may even have some mic info for you or at least a wiring diagram of the mic connector so you can get something brewed up yourself.

 

P/S - Add on:  This company was a servicing dealer for that type of repeater. If all else fails, call their service department to see if they have MIC info for you...

 

HUTTON COMMUNICATIONS

2520 Marsh Lane

Carrollton, TX 75006

P 877.648.8866

F 877.762.8274

E-mail sales@huttoncom.com

www.huttononline.com

[Logan5]

Thanks for the info guys. got UPS tracking info but has yet to be updated. I thought this site was dead but looks like I was wrong. Still hopeful it arrives on Wensday. Got my figngeresed crossed.

[PastorGary]

Thanks for the update...

 

The reason that here was limited usership here was completely to do with the last forum software and glitches, when members couldn't log in properly. This new format from IP Bulletin is bullet proof and is operating very well.

 

May I just make a mention...

 

Rich D., the owner of MyGMRS.com, has a 'donations' patch at the main website.  If you have the ability, please consider helping Rich keep the main website and this forum operating, so we all can have a place to get more knowledge about equipment and to assist each other to make what we have operate to it's fullest capabilities.

 

Thank you.

[Logan5]

I will do that. in the meantime, I have to adjust to my $305 purchase. lol. Tracked out of Seacacus NJ, no local update as of yet. Been on the roof adjusting my antenna and tower. rerouted my LMR 400 to my closet top shelf, where this unit will sit. I run all of my electronics from solar power and 8XT105's in another closet so I plan to make a 24volt to 13.8volt stepdown converter so as to eleminate the internal 120volt to 13.8volt AC power converter. I find Str8 up DC/DC power to be much cleaner and more stable than AC/DC converted power. I have another question, if I wish to use my HT on the same antenna as the repeater can I use a simple "type N" "Tee" connector? or do I need something special "Duplexer" or seperate antennas? also I have read several reviews of the UVS200 claiming all kinds of problems with water intrusion and saturated fiberglass sections throwing SWR's off the chart and damageing equipment.  the UVS300 sounds like it's worse due to it's length. Thanks in advance.  Logan...

[PastorGary]

Please don't use an "N" Tee... just imagine a 50 watt blast of repeater RF entering your HT antenna connector.  Besides, a TEE will mess up the impedance and SWR.

 

You can try something like this in the following link, but don't forget to return the selector to the ACTIVE device.

 

Click > http://www.gigaparts.com/store.php?action=profile&sku=ZMF-1702&gclid=CKPk7Mb8rrYCFZFaMgodgGcAiQ

 

You can make a very effective UHF base station antenna using a  used center loaded mobile 5.4 db gain antenna and NMO magnetic mount on a piece of galvanized steel flat plate  (about 22 gauge will do) 2 feet square. You can place it just about anywhere and it works great.  I have one just outside my Rectory office window and can hit a regional repeater 17 miles away with a 4 watt Kenwood HT.

[Logan5]

That's what i was thinking. so i am gonna need two antennas then, one for the repeater and one for my HT.

[PastorGary]

[Logan5]

well I got a slam of tracking updates this morning, ending with "Out for Delivery"  an hour ago. so just sitting here watching for the UPS man. I got high hopes! Today is a wonderful day to play Radio.

[PastorGary]

Good luck with the delivery and please keep us up to speed on setup and any tech issues that you may have.  

[Logan5]

Oh yes. lol , so much for the seller packing it well. it is heavy and was packed into a box not much bigger than the unit. this unit has been serviced many times over the years and has many missing screws and bolt's so it came apart in shipping. I added new screws and bolts and got everything secured and reset both ribbon cables into the controller and it works, not very well, but it is capable within a 1/4 mile. not nearly 25 watt's worth of range. It appears the tight box damaged the cables in and out of the radios into the duplexer. so I ordered 2 new higher quality 12" LMR400 jumppers to replace them. I have no SWR meter and no way of testing if the duplexer is tuned properly. what is a good SWR meter for my needs? Frustrated but still excited.      

[Billy]

Please contact the seller with your issues before you put too much work into the repeater.  At the very least he should be allowed to correct his issues.  Ebay feedback is a powerful thing with a good seller.  Consult the more experienced and technical before you spend your money.   Bill

[Logan5]

in the middle of filling a conflict resolution form with e-bay. they want me to make further contact with the seller first. anyway, as he has a no return policy. I will only recieve a portion of my money back if any. no problem. I will work with this unit until it becomes futile. seems the jumpper cables are crimped and of low quality to begin with. so I have ordered replacements. my concern is how inportant is the length and size ie:RG58/LMR400 of the cables from the radios to the duplexer? I have seen comments concerning the length of cables when useing an SWR meter or an Antenna analizer. I chose 2x 1foot LMR400 cables with UHF male and BNC male so as to fit this configuration.  however I may wish to order a new duplexer pretuned from China with type N connectors since this is the most common connector i use. since my repeater is 25 watt's is there any reason not to get a 50 watt or even a 100 watt cavity duplexer, for future upgrades?

[Logan5]

Also I may already be experiencing flaws in the UVS200 antenna. it has been raining since yesterday and when i use my baofeng HT radio on this antenna, the LCD display fades after a few seconds of transmission, yet this does not happen on the whip antenna or even another whip I have on the roof on the end of 25 feet of LMR400, not sure what to make of it. I am heading to local Radio shop to get an SWR meter now.

[PastorGary]

This link below may have some info that is applicable to the situation... hope things work out for you.

 

http://www.eham.net/reviews/detail/2887

 

That is a dual band antenna designed for 2 meter and 440 amateur operation and may not be broad enough to load up properly at 462-467 without it looking like a direct DC short to the RF being applied.  An SWR meter for UHF is not cheap...  hope you find one.

[Logan5]

I got a cross needle meter for 60 and another 14 for a jumpper cable. still have not hooked it up, not even sure how to use it. but I think I got it. as I write I have hooked it up to my HT and I get some needle movement. will have readings after I find my glasses.

[Billy]

If "IF" you find yourself in need of an antenna, I can recommend this one.  He also makes a dual band which is what I use.   Tell him the specific frequency you want it cut for and it will come to you with flat swr's.   I have two, GMRS and MURS and 440/2meters.   The GMRS/MURS is broadband enough I still get less than 2:1 in the 440 Ham bands, not so much in the VHF arena.   This one is a purely UHF antenna and more than likely what I am going to go with for my repeater when ready.  I has a good amount of gain as well.   Good Luck

 

http://www.ebay.com/itm/111026812813?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

 

 

As a side note, a half wave of the GMRS frequencies is roughly 1 foot or 12 inches.  I have always been told that jumpers should approximate 1/2 wave of the frequency you are testing for proper measurments.   I have also read that the same theory is used in tuning duplexers and the like.   I have never tuned a duplexer and maybe one of the more knowledgeable can chime in.  But it looks like your 1 foot jumpers were a good choice.