On 11/18/2022 12:51 PM, Jeff DePolo WN3A wrote:
Could there be a difference in terminology here? To me, making mods to
something like this means actually changing parts, or board traces, or
something like that. Eliminating the notch filter would be a mod. Adding
a relay driver to either the link rx's or the back of the voter, or a
separate box, whatever, to me isn't a mod, it's part of the interfacing.
The mods to allow the receiver cards to accept a more common level of COR voltage are straightforward, take less time, and probably cost less than building up outboard logic level converters. Generally speaking, it¡¯s not a good idea to use a relay to switch very low currents unless a more expensive relay rated for such use was selected.
The JPS voters are much more flexible in most regards, but even on the used market still get decent money. I have two of the original ones and two of the later ones. The adjustable delay is nice when mixing and matching backhauls (not something I would normally design to do intentionally, but sometimes you're dealt a bad hand due to others before you not knowing what they're doing), the flexibility in interfacing is nice, etc.. In contrast, the GE's and SpectraTAC's are cheap and abundant, so it comes down to how much your time is worth if you're choosing between the options for typical ham use with RF links.
--- Jeff WN3A
OK, I get where you're going. So I can see how if someone wanted to do that, it's not a bad path. I guess I just feel much better using un-modded cards as much as possible, so I can just pop one in and set levels if I need to.
The relay drivers I had were a pile of boards and parts needed that were left over from a company I used to work for that doesn't do LMR anymore, so they would've gone in the trash. Just a simple less than 1" square board, 2 transistors, a few misc parts, and a little relay. The one I have now has been running a couple years quite nicely. I can't say I ever heard of an issue switching low currents with a relay, only high currents. Huh...
