RF connector ID

[Jester]

Can someone identify this connector type?

This is a Tallysman Wireless TW3030, the datasheet states it's available with either a TNC or N-Type connector.

I need to source a cable from this to a GPSDO board with a Type F connector

[Richard Crowley]

Essentially impossible from that photo without a better shot of the end with a measurement reference included.
Unless somebody has that exact antenna and already knows,

[ataradov]

Depending on a scale, it looks a lot like Type-N.

EDIT: Although may be not. It is hard to tell.

You should probably post a picture of an actual connector.

EDIT2: I guess it looks more like TNC, since Type-N would have shorter threads.

[CatalinaWOW]

I assume you have already dealt with, or have a plan to deal with the note on the side which says "bad".

[CatalinaWOW]

If you have a caliper you can use the following to determine the type.

N-type Connector

According to Amphenol the N-type is the Neill-Concelman connector invented in the 1950’s. The N-type is a large version of the TNC. The N Males are about 0.825 inches (20.1 mm) outside dimension vs. 0.630 inches  (16 mm) for the TNC. The N-type is a thread on connector with a long neck. This provides excellent EMI protection. In many cases > –90 dB  for RF leakage which is dependent on the manufacturer and cable type.  The N-type comes in 4 flavors. The standard 50 Ohm, the 75 ohm, the reverse polarity and the 18 GHz version.

[TheSteve]

That is a TNC connector.

[targit]

Agreed, TNC by the look of it, (almost) universal connector of the in car mobile phone transceivers from the olden days.

[TheSteve]

And very common on GPS antenna's. My Trimbles all use them.

[Jester]

I'm now looking for an appropriate cable (TNC to Type F). I should only need about 10' for clear sky.

RG174 is 30dB/100'
RG58a/u is >18dB/100'

Any suggestions on cable type and or a good source to purchase?

I could purchase this and cut off the antenna and add a Type F connector, 3dB loss is probably okay?
http://www.ebay.com/itm/Antenna-magnet-GPS-Active-TNC-male-plug-90-1575-42MHz-3-5V-RG174-3M-cable-/262649648949?hash=item3d27239735:g:D20AAOxyNo9Sobhi

I will be using it with this style GPPDO

http://www.ebay.com/itm/182158031746?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[Howardlong]

Be aware that most (but not all) F connectors are for 75 ohm coax, the coax cables you mentioned are 50 ohm. N types are also mostly 50 ohm, and I've only ever seen 50 ohm TNCs although I believe 75 ohm ones exist.

Also be aware that sticking a 50 ohm N plug into a 75 ohm N receptacle won't end well!

You can get N to F interseries adapters, I have one in my selection.

All the GPS terminations I've ever seen are 50 ohm.

Assuming the antenna's active, it'll have plenty of gain and you will probably find you can get away with quite a bit including an unmatched 75 to 50 ohm transition.

[Fraser]

I bought F to BNC adapters for my Trimble Thunderbolts and that makes cable termination simpler. The adapters are very cheap.

Fraser

[edpalmer42]

I'd use an RG-6 cable with F connectors on both ends.  Then use an adapter to go from F to whatever your antenna is.  Since this GPSDO copies the Trimble Thunderbolt in it's use of the F connector, you might as well follow Trimble's advice which is basically:  "Yes, there's a mismatch, but it makes no difference.  RG-6 is cheap and easily available.  Use it."

[Jester]

I have not received the antenna yet, although the general consensus is that the connector is most likely a TNC.  The GPSDO board has a Type F connector. Everything should be 50 Ohms.

I don't see any need for type N connectors.

[TheSteve]

I'd use an RG-6 cable with F connectors on both ends.  Then use an adapter to go from F to whatever your antenna is.  Since this GPSDO copies the Trimble Thunderbolt in it's use of the F connector, you might as well follow Trimble's advice which is basically:  "Yes, there's a mismatch, but it makes no difference.  RG-6 is cheap and easily available.  Use it."

+1

This is exactly what I'm using for both of my tower mounted GPS antenna's.

[Fraser]

If using F connectors at both ends of the cable and an adapter at the TNC socket on the antenna, you can happily use Satelite TV cable as that is good to at least 2GHz with low loss. In this scenario you need to buy a TNC male to F female adapter. Satellite TV coax is cheap due to its common use in the consumer market. A good one will either have copper braid laid over a copper foil that surrounds the dielectric insulator. The solid core is also correct dimensions as the cable us intended for use with F connectors.

I recommend self amalgamating tape is used around the connectors at the antenna as this is excellent at keeping everything watertight.

Fraser

[Jester]

I have some surplus satellite cable, I will order a type F to TNC adapter. I will update with results when everything arrives.

Thanks for your comments