Hi All,

I lost original cable of this Signal Generator EICO. While looking to buy new cable, can I just solder Coaxial TV Antenna Cable to RF output terminal (inside the generator case) at one end and two short-wired alligator clips at the other end for aligning tube radios for now?

Will this Coaxial cable noticeably affect quality?

Is there any other way (using different easy-to-find materials/cable) to do it?

Thanks in advance.

O.C

TV coax cable usually has an aluminum shield that can't easily be soldered. Aside from that, your proposed method would work fine.

Replace the connectors with BNC; that is what I did on my generator.

Then picked up some cheap BNC to alligator clip cables. I could make them but don't have soft coax.

I do have one of the mic connectors if you want to make your own cable.

I replaced the stock amphenol connector on my EICO signal generator today with a BNC. The hole was the same size and very easy to do. Then you can use the ubiquitous BNC test cables.

The connectors that match your EICO are easy to find - the Switchcraft 2501-F is the one most commonly seen. Check Amazon, Mouser or Digikey - they should be less than $10 each in singles. Pretty much any coax will work fine with that EICO.

I do not mean to get specific, but I have used solid center conductor cable and found it too stiff for test leads. Not wanting to opt for the "finest" flexible test lead I tend to lay a hot soldering iron on cables occasionally I tried RG59 A/U with stranded center conductor. Note there are variations and some are more flexible than others. Stick with the "microphone" connector that way your cables will be somewhat dedicated to that "type" of instrument.. You may want to create some sort of "False Antenna", that could be part of a cable assembly.

Overall, be sure that some sort of series capacitor be used to prevent B+ back-feeding into the resistors in the attenuator and roasting them...

GL

Chas

+1 on changing the connector to BNC. I make cables for applications like this using RG-58C/U coax ... the center conductor is stranded and the shield is easily solderable. RG-58C/U is commonly available and I've found it to have all the flexibility I need.
R/ John

Thanks all for your replies. I got a BNC and a BNC to agitator clip from a local electronics store for $8.00 total and replaced the old connector.

O.C

I haven't changed anything with an Amphenol mike connector to BNC because the ones that I have are part of my collection and are not used (my father built some of them from kits in the '60s). Anything that I have with an Amphenol connector has long since been retired after being replaced with an instrument (mostly GR and HP), and those already have GR 874 or BNC connectors. If you are regularly using something like an EICO signal generator changing the connector to a BNC might be a good move.

The nice thing about the old Amphenol microphone connectors is they can easily be repaired in the field, whenever and wherever necessary. All you need is a small screwdriver and a soldering iron. Most modern BNCs are crimp-ons which means you have to cut them off and replace them when they fail, not as convenient in this day and age when you cannot just run down to the local radio store and buy replacements and the paraphernalia to install them.

Yes solder-on BNCs are still available but they are pricey and most have to be ordered for the specific cable you are using. They are not designed for situations where the cable is moved a lot and may need frequent re-soldering if used on test leads. Screw-on BNCs are beneath dignity. One other thing to keep in mind: BNCs are only reliable if you get ones with gold plated center pins and center contacts. Many of the cheap ones have tin plated pins and contacts, and it's only a question of when they will oxidize and become intermittent, not if.