German Army issue antenna for the SEM-25 radio - Steel Soldiers::Military Vehicles Supersite

comdiver · 09-13-2009, 21:13

I just came across German Army issue antenna for the SEM-25 radios. The discription said they work from 25mhz - 70mhz. They have a tuning box with them but there is also a remote unit that tunes the antenna which isn't incluided. I would like to use this with a CB set, 27mhz. The antenna needs to be setup and left alone. Can I do this, how?

B3.3T · 09-13-2009, 21:25

You just need to purchase/borrow a tuning unit and modify it length to correct tuning range.

tennmogger · 09-14-2009, 16:54

B3.3T is right, you just need to tune the antenna to be an electrical quarter wavelength at 26 to 27 mHz (pick a channel).

Just verifying, you did not get the tuner, right? Is the antenna you do have a simple 2 piece ceramic base insulator and rubber covered spring? Any pictures?

(edit) If you did get the tuner, that tuner steps through the bands with the radio as it changes. Steps are in 1 MHz increments. To use the tuner plus antenna on a specific frequency, the tuner has to be tuned within the band for that channel. That requires a little tuning tool and the use of a tuning set (have one, will have to look in the shop) but it can be done. Then the tuner would remain on that tuned frequency and passively make your CB happy. However, there will be signal loss in this tuner because it's making a non-resonant antenna 'look good' to the radio. You will get a better signal from a 1/4 wave whip.

If you have just the antenna, it's like a NATO AB-15 base and uses the screw together whip pieces (MS-115 to 119 etc, or AB-21 to 24 series.. Select a whip combination to be about 102" long, or (regrettably) trim the end off the top one to get the right length plus a little, then fine tune with an SWR meter.

If this antenna is something unique and special to the SEM-25 (which I have in my Unimog Radio truck), would you be interested in some kind of trade?

thanks,

Bob

Quote:

Originally Posted by comdiver

I just came across German Army issue antenna for the SEM-25 radios. The discription said they work from 25mhz - 70mhz. They have a tuning box with them but there is also a remote unit that tunes the antenna which isn't incluided. I would like to use this with a CB set, 27mhz. The antenna needs to be setup and left alone. Can I do this, how?