hf tuner

[ziggystardust]

i have an old icom hf on my yacht ive had it twenty yrs lived on her all that time i modded the radio for all band tx/rx never had a licence didnt know i needed one till about ten yrs ago any way just found out i should realy use a tuner with it for better performance it has always worked fine without, can any one reccomend a good one to try, hippy bum saior.

[bill good]

You may not need one!! The "old" radios with fixed frequencies use to have the loading coils inside set when installed but needs to be tuned for the aerial system & just a aerial post comming out of the set. If a tuner unit is required then the feed out of the radio would be a coax lead. Some of the sets also had "load & tune knobs" on the set. This is where "operator instructions" are needed if you do not understand the proceedure. Does that help?

regards Bill Goodward

[ziggystardust]

Originally Posted by bill good

You may not need one!! The "old" radios with fixed frequencies use to have the loading coils inside set when installed but needs to be tuned for the aerial system & just a aerial post comming out of the set. If a tuner unit is required then the feed out of the radio would be a coax lead. Some of the sets also had "load & tune knobs" on the set. This is where "operator instructions" are needed if you do not understand the proceedure. Does that help?

regards Bill Goodward

thanks very much Bill seems i might not need one after all i just got a bit worried when a friend said i should have one, cheers , jonny.

[maxingout]

It wouldn't hurt to put and SWR meter in line at the transmitter to see what the standing wave ratio is.

It can be hard on the radio if there is a lot of reflected power coming back down the antenna and hitting the finals on the transmitter. I lost an Icom radio because of damage to the finals from reflected power. When I got an Icom automatic antenna tuner, my radio ran much better.

[sluissa]

from what I hear, very old radios, especially the ones that used tubes, were much less susceptible to damage from relatively high SWR

While high swr isn't good for any radio, you could just say that the tubes were much more forgiving than modern transistors

but yes, get in contact with a local ham if you can find one, they'll most likely be nice enough and interested enough to help you test out your rig, assuming you're not using it unlicensed.

If you're doing anything not strictly within the rules, you should probably just not mention it, or better yet, cut it out, since most hams I've met have been pretty strict about following the rules... not so much about turning you in, at least not at the first mistake, but they will nag you about it a bit...

[bill good]

No all transmitters have to be matched to the aerial (load) correctly. The Units with fixed frequencies could be preset inside to suit the antenna & frequency. Some variations had a separate tuner unit with a coax cable connection to allow more installation options. There is no SWR test for an open wire connection. A hot wire amp meter was used to meter aerial current. The set would have to have a coax lead going off to some type of aerial tuner unit (auto or manual) The sets often had a tune position & light to adjust the loading manually.

Regards Bill Goodward