Amateur (Ham) Radio BS and Callsign Thread!

So if I was using my F8HP for APRS Tx/Rx, would I be truly benefiting from getting the below antenna and mounting it to the roof as opposed to a 16 inch Nagoya whip antenna? Not sure if the equipment would be worth the cost for an 8 watt radio. Seems the Nagoya gets 2.5DBi gain vs the below at 3.0

https://www.amazon.com/dp/B00MANF3L6


Also, does anyone here have the Yaesu 88/8900? I'm looking for the faceplate dimensions.

 

That's a quite an expensive antenna for the application you will be using it for, in my opinion I was going to suggest a cheaper alternative, the antenna that I'm using, it has a little higher gain, lower Watt handling, but it has an NMO base and it's not a fold over antenna. And most important it's not a Diamond ...
BROWNING BR-180 Amateur Dual-Band Mobile Antenna

$43 BROWNING BR-180 Amateur Dual-Band Mobile Antenna

https://www.amazon.com/dp/B003H3DTGE/ref=cm_sw_r_cp_apa_i_I4uKCbK2PDKAZ
I still use mine on the magnet, and it works okay for whatever I use my radio for now.
Also, I believe it will make a hell of a difference if you take your antenna outside of a vehicle, if you use your ht as mobile aprs radio. It made a big difference for me in audio/phone.

 

My bad, I meant to post the NMO one. I need the foldover design to fit in the garage, so that's a must. It is overkill for sure, but I think it'll stopgap until I find a better radio that I want to use for APRS. It also will match the antenna I use for 2m/70cm currently.

Why the dislike for Diamond? I have had mine for a good while now, and it hasn't let me down in the least.

 

Oh I have absolutely no dislike for Diamond. I didn't mean for it to come across that way. I was just pointing you to a cheaper alternative, but unfortunately it's missing the most important feature, folding over capability

 

I figured you may have been playing at the budget angle, but I took the other route. I appreciate the suggestion. Honestly, gonna be holding off for a bit until I figure out what I REALLY want to do for a comms setup.

 

Are you referring to a whip on the radio itself? If you are trying to compare a whip on the radio vs an external antenna, there is no comparison.

 

Antenna theory is one area I was never super confident or knowledgeable in. I know a 17 inch antenna external is gonna perform worse that a 40 inch antenna, but that's about it.

 

That isn't nessesarily true. Different wavelength antennas have different radiation patterns. So a 40" (5/8 wavelength) antenna has more gain low to the ground, but if you are in a weird situation where you are in a valley and need to get some vertical height to reach a repeater up on a mountain, a 1/4 wave might work better. This chart shows the difference between a 1/4 wave vertical (approx 17") and a 5/8 wave vertical.


Keep in mind this image is showing perfect antennas. So, grain of salt, and all.

So like a lot of things in ham radio, it depends. I don't know if you commonly find yourself in that situation, but a 1/4 wave may be better. Also, as far as straight gain goes, 0.5 dbi of gain isn't that much. Gain is measured logarithmically, so 3dbi of gain is 2x the power but 2dbi of gain is 1.58x the power. As it turns out, 2.5dbi of gain is 1.78x the power. So you are only getting, a 12% increase. You wouldn't even notice that if you measured the received signal on an S meter.

 

Utah is pretty flat, so for most purposes a 5/8 is better for my purposes. Especially when the APRS digipeaters are across the valley from me. But we do have some nice mountain ranges that could benefit from a 1/4 wave.

Is there a good resource for measuring antenna interference distances as well? Trying to run multiple antennas simultaneously on the roof seems like a hazard for overload. Im thinking of a 5/8 wave on the front corners of the roof rack so ~47 inches apart. Primarily run on 144.390 for aprs and 146.460/520/620Mhz for voice

 

Thanks for this great explanation!

My previous suggestion was based assumption of Nagoya antenna being a replacement for rubber ducky, not external 1/4 wave antenna...

 

Well you are right, it is a ducky. But i usually put my radio up on my roofrack when parked and beacon external. In cab would be total garbage.

 

I might need a suggestion for an external speaker. Right now I'm using a Midland 4ohm speaker Midland 21-406 Deluxe CB / Amateur / Marine Extension Speaker

$30 Midland- 21-406 Heavy-duty 20W Deluxe External Speaker - Swivel Base Bracket Works with Midland CB and MXT radios 8-OHM Sound System 3.5mm audio plug - off-roading, farming - 5-FT Cable

https://www.amazon.com/dp/B000246VPM/ref=cm_sw_r_cp_apa_i_.QwKCbFWDH0WS mounted in driver's footwell. Works well while stopped or in traffic, but turned out pretty useless while driving at high speeds. Might need amplified speaker.
I have Yaesu ftm-400 which calls for 4ohm speaker. Now, I've seen some amplified speakers, but they had 8 ohm impendence. So. Should I worry about it since they're amplified?

 

I took the face off of this MFJ speaker and mounted it to the headliner near the upper console. Right near my head, can hear it regardless of wind and road noise.

 

If you are outside, I would give the Nagoya a shot, it might work and it's a whole lot cheaper. Plus it requires no wiring.

 

I did the same but I kludged it together with a speaker I found on digikey. No issues at all.

 

I have. It works decent if it has relative line of sight and not in a building or a car.

 

Do you guys have any pics of your concoctions?

 

The FTM-400s (both the early one and the XDR) do behave much better with 4-ohm speakers but will drive an efficient 8-ohm speaker tolerably well -- Remember though, the 400's, like the 100's, use a ground-isolated stereo output, which is why Yaesu includes a ground isolated stereo to mono adapter with the radio. So, whatever speaker you choose, do use the provided adapter, or address both the plug in the radio and the stereo to mono conversion so that you'll get best possible power to the speaker and not damage the 400 with a mono plug.

 

Head unit on a Lido mount. Radio under passenger seat makes it easy to run a wire up the column. Simple took the front half of the speaker, cut a small hole for the magnet to fit through the headliner, and poke the screws through from the top.



The other piece there is the CB

 

Thanks bud. Come to think of it, I might have seen your setup before .
I will have to think of some alternate way, I don't have a all that real estate up top to even attempt cutting speaker holes in headliner .... Sunroof issues, lol.