On Sun, 6 Jun 2010 01:19:04 +0000 (UTC), "Geoffrey S. Mendelson"
wrote:
That's what I do. Most of my cables are NOT terminated with UHF
connectors. If I need to go to UHF, I use an adapter.
They are also hard to get and expensive.
My guess(tm) is that they are less expensive than oddities such as an
N-connector for RG-6a/u. They also have the advantage of being
reusable. When you destroy your coax cable, just unscrew the adapters
and use a new F connector.
I sometimes have to make my own adapters. It's not because the
adapter is unavailable or hard to find. It's because the accumulated
length of the connectors and adapters can get quite long. There are
also mechanical considerations, where an N to SMA adapter will surely
break at the SMA when the heavy cable is bent. For SMA and Mini-UHF
adapters, I sometimes use short pigtails to act as a strain relief.
OK, So where do you get your adaptors?
It varies. Once a year, I got to one local hamfest and stock up. I
like to see the connectors to make sure they're not junk. I typically
buy about $150 worth every year. Much of it disappears during Field
Day. The problem is that most of this stuff is nickel plated. Nickel
is fine for systems which are not potentially affected by
intermodulation issues. Therefore, I'll use them at home, Field Day,
other hams stations, and my mobile. I won't use them for repeaters,
mountain top sites, and microwave links.
http://www.amphenolrf.com/simple/PIM%20Paper.pdf
http://www.repeater-builder.com/antenna/pdf/andrew-braid-over-foil-imd.pdf
http://www.repeater-builder.com/antenna/pdf/recommended-coax-and-connectors-for-iden.pdf
For repeaters, I use silver plated connectors, when I can get them.
Gold plating is an option, but under the gold is a layer of nickel,
which worries me a little (most of the RF flows on the surface). Tin
plate also works. I buy most of my connectors from RF Industries:
http://www.rfcoaxconnectors.com
Their mix is really bizarre. They offer Nickel, Tin, Silver and Gold
plating, but not in every type of connector. For example, F adapters
are available only in Nickel or Gold, while UHF connector are only
available in Nickel and Silver. Trying to avoid dissimilar metals is
difficult.
Other sources are eBay, various online dealers, the local electronics
sto
http://www.santacruzelectronics.com
the local cable company, and the local DTV satellite installation
company. The latter are my best sources of RG-6a/u and F connectors.
I once obtained a free bucket full of filthy connectors that someone
had left in the rain. Rather than clean them, they went to me,
instead of the recyclers. There were literally hundreds of F
connectors in the bucket.
If you're working on the HF and VHF bands, you can probably just
solder two connectors together to make an adapter. I have a bunch of
BNC to UHF adapter I made this way. The BNC panel jack fits nicely
into the PL-259 connector. The losses are not signifigant, even at
microwave (2.4GHz) frequencies:
http://802.11junk.com/jeffl/antennas/connector-loss/
I've done 8 ft chains of adapters with similar results.
I don't know what to suggest. It sounds like getting someone in
Europe to throw together a collection of connectors for you seems
easier than importing them one at a time.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558