JohnE

so its a grey zone.

Bill, good to hear. Logan - glad you got a free tune. I always check for a call sign when someone asks to use either of my machines. I also do a direct FCC search even though Rich has it linked on here I know in my searches I have come up w/one or two that don't exist. direct FCC search link. http://wireless2.fcc.gov/UlsApp/UlsSearch/searchAdvanced.jsp;JSESSIONID_ULSSEARCH=qT2vJsQGDv2mn0vZ1Z1W4n38hDPVKJQ9lvqLGVJNhWwwCTJfJ1Sz!740247892!NONE

you could always make a timer on a bread board w/relay to kill the PTT. just a thought.

NICE!

I'll have to look and see if I can find the notes we had on a Plectron toner for one of our VFD's. it was an old 70's vintage plectron wired through the MRTI I think on an MTR 2000. getting the audio is the easy part, making PTT no too hard either, it where to put it.

I had a user on my 650 machine using them. I can't speak as to the durability of them but they didn't sound too bad.

glad to see you made some progress. she or they should be talking to their radio provider at this point. did you make them aware that they should be on commercial/land mobile freq's? also on a side note I have heard from more than one source that the FCC is not only fining violators but also the shops that set them up. I don't know how much truth there is to this but like I said I got it from more than one place. I use to be able to make a call to verify stuff like that but my connection to local field office retired yrs ago. that process can take 6 months or more depending on the shop , coordinator, freq's available and time to process the license. just sayin'

you have to be absolutely sure of who it is before you approach them. make recordings/video of it and be totally sure of the freq they are on. find their PL's and key the machine yourself to double check. seeing as you seem to have announced yourself already you can tell them over the air that you will be going to the FCC, site what rule they are in violation of and let them know what the fines are going to be.let them know they're being recorded too. w/that in mind do a search for GMRS fine in Scottsdale AZ a yr or 2 back for an auto dealership who got hit for IIRC $20K. as an Individual I would not approach the business in question personally. w/recordings/video in hand I would then approach the FCC. PG your thoughts. **EDIT** FOUND LINK http://forums.radioreference.com/gmrs-frs/202372-lexus-dealer-az-nailed-fcc-unlicensed-gmrs-use.html

good. those should have a loss of 1.5dB sometimes less and around 75dB of isolation. you'll be good to go w/those.

good to hear man.

Glad to see you took a stab at doing the VCO's not as tough as you thought. did you tune the power output as well? you have a PM.

do us a favor measure the output before and after the duplexer, I'm curious about how much loss it has. if its a good tune your losses will be ~6W based on the 30W its suppose to do. this was one of those Chinese filters ,right?

you have LMR 400 witch IMO is a little better that you average 213 cable. losses at 450Mc by the book are 2.5db/100'. in the grand scheme of things you total losses (duplexer/line/insertion) will be ~2.5dB so any antenna you can get to get over that would be good. I personally use fiberglass sticks w/5dB gain typically, they can be had for $100. on control's I use 5 or 6 element yagi's. one of these yrs I'll put a set of yagis in a stacked array like the folded dipole's just to see how it will work for s&giggles. one of my RF engineer friends thinks I'm out of my mind, but hey there nothing wrong w/experimenting. link to the propagation software http://lrcov.crc.ca/main/

it should be exact. can you post a pic of the filter in question? also did you solve you "hum" problem? a crank up tower would be nice but you still have to climb to cange antennas. I'm still in the process of putting somthing together for my machine at my house. looks like its going to be 50' of galv EMT w/guys. don't really want to get involved w/ree climbing. Gary, what antenna is that w/all the gain?

bad filtering on the supply. try a different one and see what happens. just curious PM me w/pl or e mail me some PL's if set too high will cause the same problem.

to check this "buzz" since I can't hear it I'll have to guess as to what it could possibly be. check voiltages and drop while keyed-if good put a dummy load on TX side and see if you still have "buzz" if no one of 2 things - bad antenna or cable- not enough isolation TX to RX. you also might want to try the reverse of that too just to confirm. are your antenna's verticly or horizontaly isolated? another possibility is........................................wait for it, there is a repeater w/same frq/pl your using although not out of the question but still possiblity I don't know how urban or rual you are but in know on the frq I use in NYC it took me some time to get PL's that didn't key other machines. from my control point there are six I can hit cleanly and 2 have the same output tone.

Bill has a point here. what is your game plan and what do you need to cover?

you didn't post a price for the SM50 set up. what I can tell you is that the SM 50 came in 2 power ratings 25W/40W I hope he is using the 40W turned down. the RX sensitivity is is typically .30uv. .25 is not a strech but I haven't seen too many Motorola'a do that out of the box and this radio is better that 15ys old, just sayin'. other than that they are pretty reliable radio, I have a couple myself. a decent duplexer will runyou ~$200. I can't say how good the "cheap" duplexer's are on e-bay but I have heard that they have quite a bit of loss. that said you should ask seller if he can provide a tuned duplexer w/setup. if he's saying its all tested and certed by a Mot shop I don't think asking for a duplexer would be out of the question. don't forget a pair of 6" jumpers too.

like Gary said 2-3 seconds is farly standard. as for the fan if it can be set themally or on TX only that would be the better option. you extend the life of the fan and if the unit is in a controlled enviorment it doesn't need to be on all the time. both of mine are set at 1.5 sec hang and thermal on the fans. call sign interval is 30 min. I know on the commercial side call sign has to go out at least once an hr most are set to 15 min intervals though.