Lemo Mini-Coax Connectors

[ericwallace]

I'm new to this forum but a constant lurker/occasional poster to ramps so hello all.

Some backstory on my question:

I bought some used older Microns (500 series) a little while back. They have been working pretty well so far but I really don't trust the antennas that they came with. They're pretty flimsy and I get some range issues at distances shorter than I would prefer(using Lectro sharkfins into an RF distro/filter feeding 4 recievers). I'm sure that some of the range issues is because of the equipment itself (the manual doesn't list the transmitting power anywhere). A friend of mine had a similiar situation with some older Audio Limited gear that had the same kind of floppy whip antennas(SMA connectors tho). He replaced them with the Remote Audio miracle whips and it gave him a significant range increase. I'd like to do something similar but the miracle whips don't come in Lemo Mini-Coax. I plan on emailing them to see if they could possibly make them for me but in lieu of that I'd like to get some of the connectors and build something myself.

The only problem is that I have no clue where to get them. I've poked around online quite a bit and have had a lot of trouble finding a source for them. I'm sure that some sound houses might have some in stock but I know how they tend to gouge on Lemos and I'm trying to keep my costs down.

Short of calling distributors(which is my next step), anyone know any places that would have them?

Thanks.

-e

[John Steigerwald]

Hey Eric,

Try Mouser Electronics or Digikey.

Both carry LEMO connectors, tho I think Mouser has a better selection.

Is the connector you are looking for listed HERE?

[ericwallace]

Yup, thats them.

I'm pretty sure I scoured DigiKey's catalog and either they didn't have them or I couldn't find them. I didn't know of Mouser.

Thanks John

-e

[jason porter]

Eric,

What is your receiver model number?

I assume the transmitters are Tx500's...I believe the RF output is 50mW.  You should check to see if your Tx antenna are tuned to the correct frequency and that they are not intermittent.  My local audio repair shop verified my antennas were the wrong freq and had intermittent connections on 3 of the 4 antenna connectors (BNC)  Also, are they fixed frequency? are you having intermod problems between 2 or more of the transmitters?  I added a dipole antenna to my old Micron system, and my range went from 100ft to over 300ft!

You can get right-angled transmitter antennas (very low profile, but probably even MORE expensive than the regular antenna)  With these you have a much lower chance of breakage.  Here is a picture-

[ericwallace]

Thanks for the note on the RF output.

My transmitters are 500 series with 2 switchable frequencies. I haven't noticed any intermod issues and by and large I get very little interference. I do begin to get signal dropouts though. The antennas appear to be the ones that the system originally came with so I suspect either a broken connection or that they aren't tuned correctly. I've seen the right angle connectors before but I really don't like the idea of them. They might be okay for the floppy whip kind but I don't know if I (or talent for that matter) would like using them with a more rigid antenna.

The lectro log peridoic antennas do a great job extending range but I still have a lot of issues if the transmitter is blocked by a body at long range. I guess that probably has a lot to do with the transmitter power than anything else. Though. By and large I'm very happy with them for about 90% of the situations that I'm in. I was doing some follow car work last week and was having a lot of trouble so I think I might need to get some higher transmitting power lectros or something.

-e

[jason porter]

It has been discussed here and on RAMPS many times...don't be fooled by the output power of a transmitter.  100mW is not "twice as good" as 50mW.  The human body is very efficient at absorbing RF energy...try moving your antennas into a position where they have a better line-of-sight with the transmitter.

When using transmitters in a car, your best bet would be to get the transmitter away from the body (the person, not the car) and up high.  Even better would be to remote mount a dipole or sharkfin onto the "off camera" side or the roof of the car (if you can)  The cars electrical system and the engine itself can cause interference and dropouts!

With the Microns, I have had similar problems when the antenna is "squashed" between a person and a seat, but the Lectros (for some reason) seem to handle the situation better!

[ericwallace]

For the car stuff I was set up in a lead vehicle(no process trailer on this show) with mics up on the visors and the transmitters taped to the ceiling of the car. I had the sharkfins rigged up outside the lead vehicle on fleximounts running to my gear inside. They worked mostly well for ranges up to around 200 ft. I was having trouble with one of the transmitter so I had a line of sight kind of rig up that worked exceptionally well.

The time when I did have the issue was where there was a very long dolly shot and the TX was behind the talents back on the far side of me.

I had a glitch today where talent was standing a few feet in front of my antennas  with the transmitter in line of sight to the antennas and I was getting very little reception (1 LED). I did a battery change and it didn't help. I then did an antenna and frequency swap (there was no indication of RF interference at the location though) and that did the trick. I kind of wish I had tried them separarently to find out what the exact cause of the problem was.

-e