> >In the past I've actually routed the shielded CTCSS endode > >audio source wire through chassis and cabinet/box holes > >and in this case I used the feed through-capacitor method. > Yes, but if you run a wire into a box through a hole, you > might as well take the lid off too, as that wire will act > just like a coupling probe between the boxes.
Depends on how the wires are done... I understand what you're trying to convey... but it's not been a problem/issue in this example. > > > >The Hamtronics Receiver COR/COS output is active high, > > > > which I don't like one bit. > Oops - that should have been "...I used active low COS as > well." I also used active low CTCSS, but I still do today - > that never changed because the RLC-1 controller only works > with active low CTCSS. In cases where I run into active high logic... I change them to active low before they leave the box for the big world. I've run into a number of Ham devices (the above mentioned Hamtronics Receiver and the CAT Auto RLS/RBS-1000 unit) with active high logic and it's just more sane to convert everything over. > >I like active low logic for a number of reasons and personal > >preference. In a situation where the controlling device loses > >power, there is a potential for the transmitter to key up. > If the RX loses power, the logic outputs could pull to ground > as well - depends on the design. In my case, using opposing > polarities on COS & CTCSS appears to eliminate the possibility > of both becoming spuriously valid. If power goes away... the active low device normally would stay high impedance (high isolated state) and I can be more easily assured the trailing controller remains in a resting state. > >For this project... I only used the feed-through capacitors > >for everything. The wires at the rear of the controller get > >into the controller via a DB-9 plug but nothing on the chassis > >or RF deck. I stopped using small Anderson Power Pole connectors > >because of all the grief they caused me on the commercial > >radio side of my life. A lot of people like and use them but > >I don't trust or use them anymore after a few 10 hour days > >sourced back to intermittent small power-pole connectors. > > Uh oh, I hope I don't run into that problem. I began to > standardize on the PowerPole a few years ago & have about > 80% of my equipment converted. Before that I direct-wired > everything, but that just got too painful every time I needed > to swap something out. For a short time I started using > Molex but the current rating of the easily-obtainable > versions was only 8 A - not enough even when doubled up. Some people seem to have decent results with the Power-poles... and I can and do sometimes use them in legacy (already installed) situations... but I have my own way of ensuring they don't go intermittent, which I don't apply/use in the commercial radio world. I don't normally like or use Molex connectors for any serious current requirement. > Up to now the only negative comments I've heard regarding > the PowerPole are related to their non-locking nature. I've > found their inherent retention force to be more than > sufficient for all my applications, both repeater & > mobile. I know that PowerPoles (& probably almost all other > DC connectors) are NOT designed to be hot-mated, which could > cause contact problems. Sometimes it's unavoidable, but > I try to prevent it whenever I can. I just end up removing them from the path and do as much direct wire as possible. I haven't had to revisit a cranky intermittent power-pole since. > >Unless I'm sure there's going to be a lot of shear RF at the > >repeaters location... I take the simple and easy route. Even > >with a broadcast station nearby (but not in the same value) > >I didn't feel the advanced filtering techniques were required > >and so far, so good. > > When I box a RX, it's usually because I'm having an > interference problem due to insufficient shielding. So > I want to be darn sure I don't have to do it again. > Bob NO6B This example used a supplied bare receiver and transmitter boards. I put them in to acceptable boxes and wired things up. Lo and behold it all works very well and I'm on to the next cluster _______ . I'll hopefully be posting part 3 of this saga in the near future. Smell the Dayton Brats (Brauts) defrosting... cheers, s.
