Siltronix FS-07 Antenna Tuner

[BigLion]

Does anyone know how to use this tuner? I attach a photo of the unit. I have no idea how it is supposed to work. I assume other models are similar but any guidance on its use would be much appreciated!Be safe out there!



Frank

[MDYoungblood]

It's a pretty straight forward tuner.
The meter is controlled by the FWD(forward)/REF(reflected) switch and the CAL (calibrate).
The OUT/IN switch controls the TUNE above, switching it "out" makes a straight through connection, "in" feeds through the TUNE section.
To tune, first set the SWR (out/in switch on "OUT", switch on REF and adjust CAL to full scale on the meter, switch to FWD, should read the SWR on the scale. If the SWR is within reason no need for the TUNE. If the TUNE is needed, switch to "IN" and adjust the 2 knobs to achieve best SWR, doing this will require adjusting the SWR via the CAL, FWD, REF, several times.
Just to let you know if you don't already a tuner just fools the radio into thinking the SWR is fine but really everything from it to the going to and possibly the antenna as well is still out of wack.

3's

Greg

[BigLion]

Thanks Greg! what causes a high SWR? My rig is connected with USA made RG-8U cable, solid copper ground rod, and an Anton A-99 antenna. no extended cable coils or anything. Any assistance on how to lower SWR would help. I know high SWR can damage the finals, especially in a linear amp.

[nosaj]

First you need to tune the antron 99 if you have not done so. There are 2 metal rings that will screw up or down so you can tune it. I have mine tuned for the 10m band.
A bad cable can make high swr , one I was given tested fine , but one day I was using it with 2 meters my swr went bonkers the wifi in the house went nuts any time I would key mic. Troubleshot it to the cable , pulled ends off and someone decided not to solder the sheild to the connector. I asked the guy I got it from who got it from an SK who was know for not doing that. Once I soldered the braid to the connector life was good.

nosaj
N1EBC

[redcentinela7]

Big Lion, did you learn how to use this antenna tuner ?

What is your SWR right now ?

If you have a good system ( coax, proper antenna, etc ) , you should not be using an antenna tuner. Antenas like A99 should have SWR below 1.5 ( around 2 Mhz of bandwidth ). It should cover all 40 CB channels without any problem.

They usually cover from 26.000MHz to
28.000 MHz without problem, so no need to use a tuner. Tuners are usually used for multiband purposes. For example, you can use an A99 on 10m, 12m, 15m with the assistance of a tuner, a good one of course. The one you show appears not to be a good one.

Like MDYoungblood said, an antenna tuner fools your radio, it makes it happy, because it sees a 1.1 SWR, when the reality is that you still have an inefficient system. You will get radio frequency out of your antenna, but not the maximum.

[Rfinisd]

Hello, know it's old post but does anyone know the wattage limit on this antenna tuner?

[MDYoungblood]

Hello, know it's old post but does anyone know the wattage limit on this antenna tuner?

They were made to go with most model Siltronix radios so I would say the maximum would be less than 150w. From it's size, the air caps inside couldn't be too big so anything over that would arc.
JMO!

3's

Greg

[The DB]

I couldn't find anything on this device specifically, but MD is right, it can't handle to much power, one thing about this type of device is the components that are able to handle larger amounts of power tend to be rather large. I have a tuner that is s little bigger than this and its rated at 300 watts. I wouldn't push that one past 100 watts or so until I found some documentation on it.

The two knobs and a switch below them says a lot about its likely layout, so I'm going to guess it is an L network with a switch to change how that L network is wired. I would love to see a good picture of the inside of that tuner if possible.


The DB