Base Super Scanner upgrade pwr handling?

[TIN_CAN]

I have heard you can upgrade the components on a super scanner antenna to handle more then 500w? Is this possible to do? I have a line on some cheap super scanner antennas, he has 2 complete and a 3rd for parts for $200 canadian, anyone know of such a mod?

cheers!

 

[Dmans]

TIN_CAN,
A quick peek at the manual for this antenna tells me the limiting factor for input power would be the switching relays and the coax cable used between the relays and the elements.

The installed coax cables would be the first thing I would upgrade just because of their age. Attention to factory lengths of these cables is a crucial component of the antennas ability to perform as designed. You should probably take into account the velocity factor of the factory cables and convert those measurements to your replacement cables.

Higher amperage relays would be great insurance to stand up to 500+ watts.

I've never performed this type of mod to this antenna but I owned a Super Scanner in the 70's pushing it with a Pace CB 76!

73's
David

 

[Shockwave]

I think there were two versions of this antenna manufactured. The weak link was when the antenna is switched into the omni mode to drive all 3 elements in phase. That causes a drop impedance that must be compensated for. Early models may have used a coaxial matching stub that handled more power while most of them got a small capacitor placed inside the relay box that is switched on in the omni mode. That cap is the first thing to pop. Put a Semco silver cap or doorknob in its place to end that problem. If you use the Semco style cap I would seal over it with clear silicon to prevent moisture from migrating between the capacitors plates and let it cure for 24 hours before hitting it with any power.

 

[TIN_CAN]

Thanks for the info, I ended up picking these up and they are in nice condition, will start messing with them in the spring as we have snow on the ground already and too cold for swapping antenna's .