President Bill power wiring question

[romad275]

The radio arrived today and I was looking at it and the routing instructions. I bought this for two reasons: the small size AND the quick release snap in mount. However, the power wiring instructions make the quick release mount useless since the power wire is hard wired to the radio and is required to be hardwired to a direct battery source. So what I figured I would do is to use a Hopkins 4795 cable to make a detachable connection between the radio and the fuse holder. Has anyone done something similar?

 

[n9mxq]

That would work, I use Anderson Powerpoles.

 

[ke4emq]

I have the same radio i just put a cigarette lighter plug on the end works just fine

 

[romad275]

I have the same radio i just put a cigarette lighter plug on the end works just fine

Does the fuse for the vehicle's power port have a higher rating than the cartridge fuse that comes with the radio?

 

[romad275]

That would work, I use Anderson Powerpoles.

Those look nice but as I only need one connection, even the 10 piece kit would be overkill.

 

[mmckenna]

Does the fuse for the vehicle's power port have a higher rating than the cartridge fuse that comes with the radio?

A CB like that is only going to pull a couple of amps at the most. A 5 amp fuse would be sufficient. Most cigarette lighter sockets are rated for 10 or 20 amps.

Be careful, though...
Some vehicles have noisy power through the cigarette lighter socket. The wiring is bundled together with all the other under dash stuff, and that can result in a lot of interference issues in some cars.
It's preferred to power these directly off the battery.

If you do use the plug you linked to, make sure you wire it so the end connected to the vehicle has the positive side on the covered conductor. That way if the exposed contact touches metal, you won't pop the fuse, or worse.

 

[romad275]

Yep, that alternator whine is what I don't want. I believe there is an unswitched power terminal under the steering column of my car that will work. Also the shrouded red terminal will be on the vehicle side if I go the Hopkins route; the Powerpole is very tempting though.

 

[mmckenna]

Yep, that alternator whine is what I don't want. I believe there is an unswitched power terminal under the steering column of my car that will work. Also the shrouded red terminal will be on the vehicle side if I go the Hopkins route; the Powerpole is very tempting though.

Tapping into any under dash wiring is a crap shoot. Your choice, but there's a good reason commercial radio manufacturers will tell you to power directly off the battery.

Powerpole connectors are kind of a waste of money for one radio. The only real benefit to them is being able to swap out different radios with the same power connector.

 

[romad275]

No, IIRC, the "X" terminal in my Mk4 VW Jetta is a direct wire to the battery, bypassing the internal fuse box. However, I'll check it in the Bentley Shop Manual wiring diagrams to make sure. If not, I'll have to run a +12vdc lead from the battery into the cabin as the supplied power cable doesn't look long enough to reach the battery from where I plan on mounting the radio.

 

[mmckenna]

No, IIRC, the "X" terminal in my Mk4 VW Jetta is a direct wire to the battery, bypassing the internal fuse box.

That's good, however my concern would be what other wiring it's bundled up with. Most cars have a lot of noisy electronics. Noise from wiring can be induced into other wiring. That can be a good place for issues get into the CB and cause issues. Standard practice is to run your power feed to the battery, and doing your best to keep the wiring bundles separate.

Your car, your CB, your choice. Just passing on what I've learned over the years.

 

[ke4emq]

Guess i got lucky no noise at all . My install is in a 2019 Ranger FX4 and using a glass mount antenna with a 2 swr and no problems at all. But i only use it for off roading good luck.

 

[romad275]

That's good, however my concern would be what other wiring it's bundled up with. Most cars have a lot of noisy electronics. Noise from wiring can be induced into other wiring. That can be a good place for issues get into the CB and cause issues. Standard practice is to run your power feed to the battery, and doing your best to keep the wiring bundles separate.

Your car, your CB, your choice. Just passing on what I've learned over the years.

Actually you're kind of preaching to the choir, as they say. I have an AAS degree in electronics and worked in ATC radio maintenance for part of my Air Force career. TACP duty was part of the radio maintenance career field (even though we did zero maintenance) up until 1977 when we finally were made a separate career field. Out of my 22 year career, I only did radio maintenance from '69 to '74 and mid-'83 to mid-'84. The rest of the time it was TACP duty with Army units. However, as I said, I'll have to read the wiring diagrams and do some circuit tracing before I do the wiring. Now my Miata would be easier as the battery is in the trunk, so it is only a couple of feet to the cockpit.

 

[mmckenna]

Actually you're kind of preaching to the choir, as they say.

Good deal. Way too many take the short cut route and then wonder why they have issues. So many issues I've run across at work where someone was in a hurry.