Your Questions Answered, December 2018

Every month I comb through the comments of my videos for the best questions. This month there was a bevy, so let’s just jump headfirst into the. My video on the Subaru Outback ham radio install generated a lot of questions and comments. Both on Outback owners looking to add a rig to their car and other vehicle owners with general mobile radio installation questions.

One such question was from Rizal

Great video, I Just got an Ftm-400 and I installed it on my 2001 Jeep Wrangler. I did notice a bit of alternator noise. Anything I can do about that?

Alternator whine can be a tricky proposition. It may be a signal that one of the diodes in the alternator has gone bad and the power isn’t as clean as it should be. Considering the age of the alternator in a 2001 vehicle that could very well be the case. A common solution is a brute-force filter near the alternator. This consists of large capacitor and chokes to filter the power. But simpler methods also exist. First: take your power directly from the battery, both positive and negative feeds, so you are not subject to the vehicle’s power system noise, and second: make sure you have a good ground for the antenna. The ARRL has some additional resources on automotive radio installs.

In reply to that comment, I did receive another question as to why fuse the negative when pulling power directly from the battery. There are a couple schools of thought on this. You fuse the negative, in addition to the positive, when you make a direct connection to the battery in order to protect from wiring faults with your install. But there is also a concern that if there is a ground fault, the fuse on the negative would blow and potentially cause the energy to seek an alternative path, which would be directly through the radio. Fortunately ground faults are quite rare if you follow good practice and not route the power cables so they will bind, fray, or wear. That means using grommets to protect from sharp edges and not running power through the door.

With that said, I believe the general consensus is that fuse leads for a battery connection and fuse only positive if you are pulling ground from the chassis. But even newer cars with aluminum bodies and Engine Idle Shutdown cause more issues and K0bg has some good info on wiring modern vehicles: link below. : http://www.k0bg.com/wiring.html. My only caveat is that there is a lot of old information on the Internet about vehicle power for radio equipment and automobile technology has increased greatly in the last decade. You should follow the vehicle manufacturers recommendations for wiring accessory equipment.

Next up, are a few questions on the microphone, Mark writes:

Hi Michael. One thing I must stress in regards to mic placement when not using, make sure you don’t put it in a cubby hole in the console. I did that and found the mic was keyed up, fortunately I noticed quickly and removed it from the cubby hole. Speaking of cubby holes I have one in my Traverse that I simply cut a piece of wood that would fit snug and mounted it to the back of the control head bracket (I’m using an FT7900) so when I feel I need to remove the control head from view I just unplug the cable, pull the head out and put it in the glove box. My external speaker sits on the console under the arm rest to give me good audio. Oh and as far as the radio under the drivers seat, make sure there aren’t any heat vents for the back seat passengers located under the drivers or front passengers seats. The radio will not like the heat!

Those are all great points, if you are sticking your radio under either the driver or passenger seat, make sure you have an adequate airway, both so the radio doesn’t overheat and so the passengers in the back still receive heat from the car.

 I installed an Icom 2730 in my 04 Tacoma, and recently started using a Nite Ize Steelie to hold my mike to the dash. While they are spendy, they work well, and I can just grab and pull, rather than have to lift off of a hook, yet the magnet still holds strong enough for washboarded mountain roads.

Thanks for the recommendation, A magnetic holder like the Nite Ize sounds like a really good solution. I’ll put a link in the video description for those too.

On the mic extension cable, Scott writes:

The mic extension, is that a  standard phone cable with a junction box?

The Yaesu FTM-400XDR uses a 6 pin RJ12 modular plug and cable for their microphone. They sell a mic extension kit, but the cable is quite long and its a little pricey. I went to Amazon and bought a four foot 6 conductor cable with RJ12 six pin plugs, and a 6 pin inline coupler. Total cost, a little over $10. Other radios use the 6 pin modular connector for their microphone, so you can make a custom length extension cable for your Icom or Kenwood too.

In my install video I mentioned that I needed to add an external speaker for better audio, Chris asks:

Can you not output your audio to the car speakers?

I have made that consideration, and may do a little research on my options of running the audio through the sound system before I add an external speaker. I do like to listen to the FM broadcast radio when i”m not talking on the mobile, so I’d have to figure out if the two can coexist. But one neat feature of the FTM-400XDR is that its audio out is in stereo, so the A band goes to the right channel and the B band the left. If you do decide to run your audio through the car system, you can leave it like that, otherwise Yaesu supplies an adapter to mix the channels down to a mono signal.

Enough about the mobile install, Daniel writes:

I want to buy my first ham radio. Can u recommend a good radio for a novice?  It doesn’t have to be the cheapest. Thanks

The cheapest isn’t always the best deal, and you will get what you pay for in terms of quality. The good news is that both Icom and Yaesu have some excellent deals going on from now til the end of the year. For a handheld, I’d recommend the Yaesu FT-4XR for $99 or the FT-70DR for $159. The FT-70DR includes System Fusion which may be appealing to you if you have a Fusion repeater nearby. For a mobile, the FTM-3200DR is only $145. Even better is the Kenwood TM-281A which is 2 meter analog and 65 watts for only $132. All those prices I found at www.gigaparts.com.  If you are budget minded, the only analog Chinese handheld that I’d recommend is the Btech UV-5X3 about $59 (Although I’ve seen it sell for as low as $45 on amazon during the holidays).

https://amzn.to/2QLn7h4. I hope this helps you out.

Speaking of cheap radios, I received this comment from Stephen.

Nice test and review as always 🙂 Most “cheap” chinese radio do have a bad receiver. Can you say something about it?

Thanks for the comments. Inexpensive radios rely on Direct Conversion for detecting the RF signal. The direct conversion circuits are crammed onto one or two microprocessor chips and can be prone to poor sensitivity and overloading because they lack the proper filtering in the receiver stage. I don’t have any fancy test equipment, but I’m planning a video that demonstrates the ‘real world’ difference between Direct Conversion and Superheterodyne receiver types.

Last question, Patrick writes:

Great video as always.  I am considering getting a FTM-3200DR for home use.  What kind of power supply would I need to run it?

The FTM-3200DR is a great rig and will do up to 65 watts of power. At full power the radio will pull about 14 amps. My recommendation if you are looking to purchase a power supply is to consider a 25 amp switching supply. Street price is about $100. A 25 amp supply will give you plenty of power for 2 vhf/uhf mobile radios, or a 100 watt HF rig, so you will have a bit of growth capacity. Modern switching supplies are lightweight and inexpensive. They are also well filtered with little RF hash and are more energy efficient than linear power supplies.

And some quick announcements before I close this episode, the year is rapidly coming to a close, so that means my annual year-end countdown of the 10 best videos will here in a few short weeks. This year I’ll do a poll for a ‘peoples choice award’ so watch for that to happen either on my facebook page or here on Youtube.

Also, on Saturday January 5th I’ll be at the West Allis Radio Amateur Club’s mid-winter swapfest in Waukesha, Wisconsin. I’ll have a table selling my VHF and UHF antennas. It’s one of the bigger hamfests in the area, so if you are in the neighborhood, please stop by to chat.