Quad-boxes & mobile ham-radio operators

[Axekicker]

What does 'ham' radio have to do with our 5. 9's motors you ask? When I key up my radio mic, it kills my motor... . that's what! My question is for guys running the older 'Quadzilla' boxes and ham radios. Do any of you have a similar problem with your Quad-box (or any aftermarket box for that matter) and your ham (or CB) radios? My Quad 'race-box' was purchased & installed in 2005



I've tried to isolate and choke the RF that's getting inside my engine-control circuits and it appears the Quad-box is the culprit. When I key-up, the Quad LCD-readout goes haywire... . the motor stumbles and dies if I don't let off the 'key' quickly.



When I have half a day off, I'm going to pull the Quad-box... all it's wiring and the monitor, they see if the problem goes away... and I bet it will. Am I the 'Lone-Ranger' on this one or is anyone else having a similar problem... and if so... . what have you done to improve or correct the problem with your truck? (FYI: for you 'ham-sters', I'm running a Yaesu FT-450 @ 100 watts-out thru LMR-400 and an OPEK Ham-stick. The entire truck has been 'RF-bonded' and all radio circuits & cables RF-choked).

 

[JJPage]

I do not believe it's your Quad, lots of folks have had similar problems with a completely stock truck. If you do a search, I'm fairly certain you will find quite a bit of info.

 

[p-Bar]

Have you guys thought about shielding the box and grounding it?

 

[Axekicker]

Have you guys thought about shielding the box and grounding it?

Here's some photo's of my efforts to-date. Some of the photo's show the braided RF-strapping that I've installed on all body panels, battery and motor. In other photo's you can see the RF-chokes I've installed on electrical wires & cables along with an RF feed-thru choke on my antenna coax. That green sheet laying on my work table is medical grade sheet lead that I've wrapped all around my Quad-box... then I wrapped the box in several layers of aluminum foil; reinstalled it in the truck and RF-choked the incoming wire loom to prevent RF-migration into/out-of the box via the electrical wiring connector. Even gamma-rays won't get through that set-up! But I still have the 'stumble/cough/die' problem when I 'key-up'.



So the answer is ... . 'Yes'. I've done 'all' that, except for your recommendation to 'ground' the box. The box is already grounded via the DC-electrical circuit ground... and I 'RF-choked' the ground cable where it enters the 'box'.

 

[Axekicker]

I do not believe it's your Quad, lots of folks have had similar problems with a completely stock truck. If you do a search, I'm fairly certain you will find quite a bit of info.

I have done the 'search' multiple times since 2005... . It's true that 'some' people have this problem... but there are a lot of 'our' Dodge 'diesel' trucks pressed into commercial service (ambulances, tow-trucks, OTR hot-shots, construction, Forestry, sanitation services public-&-private... etc... ) that have commercial radio's installed in them which typically run 100-200 watts, and those vehicles do not have this problem. (Yes... I understand that most of those trucks operate at VHF/UHF freq's and I'm primarily HF... . but the basic principles are the same regardless of frequency). I was hoping that our ranks might include a commercial radio-installer who knows the proper way to 'RF-choke' these trucks... It can be done and has been done. I just need to brush-up against someone here on the TDR, with more 'smart-cells' than I to help me with the missing 'ingredient'.

 

[posey-smoker]

It is your Quad box. Mine did the same thing with my 55 watt Fire department Icom radio. I have to wrap the quad box in aluminum isolation tape including the wires as the wires were the key to killing the absorbation of the RF interference. I also had to direct wire the groud of my radio to the battery. All that fixed my engine dying issue when I Q'ed up the mic. It took all day to get it just right.

 

[WM-300]

Axekicker, nice to find another ham here. My Call sign is KS2K... whats yours ?

WM-300

 

[Axekicker]

KF7GCQ... ..... usually monitoring 40-meters mornings & evenings and 27. 385-lsb when the 'skips' running strong.

 

[Axekicker]

It is your Quad box. Mine did the same thing... (edited)

Ah! Thanks for the response. I'm going to pull all my 'Quad' connections Saturday and see if that makes a difference... . If it does, I know it's the 'box'... . and then I'll hook it back up and do some more 'shielding' as you suggested, to see if I can't 'choke' it out of the Quad-box circuits. Thanks for your input! If I have success, I'll post my results.