Amateur (Ham) Radio BS and Callsign Thread!

I don't think they are in production yet.

Adding to the idea pile: I used the backer plate from my ARB compressor to mount to my Prinsu.

 

I've seen these, had one for my CB antenna on my 04. This was my original plan for the CB antenna on the 17, but there have been reports of the tailgate rubbing the mount and causing issues so I scrapped the idea, and really like the ditch light bracket.

From what I've read, being over the hood is much better from a ground plane perspective than the brake light bracket. I can get 20-30 mi. on SSB where the antenna is now, which I think is pretty good.

 

He's talking about a mount that was meant to sandwich behind the small brake light on the top of the cab, not on the back of the truck by the main tail lights.

 

OHHHHH, I just glossed over the "3rd Brake light" part.

I think I remember seeing that somewhere earlier in this thread. I'll check into it. I assume that would work with my camper top, but I'm not positive. Will report back.

 

What kind of SWR and Range do you get with that setup? Also could you link the antenna and mount?

 

That's how mine is attached. I don't think it is ideal but I don't have access to any equipment to test it. There are some repeaters around that I think I should be able to reach but can't. Anything within about 8-10 miles seems to be fine and I'm able to hit APRS digipeaters that are up to about 30 miles away.

 

I've hit the Salt Lake City repeater for 40ish miles out at 50W tucked over a pretty sizeable mountain ridgeline. I don't have an SWR value, but the real world tests say it is more than sufficient.

 

More info about mobiles than my brain can even handle. http://www.k0bg.com/

 

You made me think about the distances. According to google earth I can reach a repeater 21.5 miles away at 5w with a lowish db antenna. I might have to do a little experimenting at lunch time with some others.

 

@BrotherBudro Why not a magnetic mount on the roof? Run the antenna coax out a floor grommet from the cab, back along the frame and up between the cab and bed. No drilling, easy routing, easy mounting and best performing mount point. I did that with a MFJ-1724B antenna and had no problems hitting repeaters over 50 miles out with ease.

 

I'm using a mag mount now with my

$40 UV-5r 8Watt Ham Radio Handheld Long Range UHF/VHF Radio with 2 Rechargeable Battery, Portable Radio for Adults with Earpiece, GV-771 Antenna, Programming Cable (3rd Gen)

UV-5r. I don't like the idea of using a mag as a long term solution due to the wearing, scratching, etc. Plus there are so many more (better) options. I'm kinda disappointed about the ditch mount. I was really hoping that was the best plan.

 

Better options for mounting maybe, but not many options that will provide better performance.

 

I have never checked the swr. The range is pretty good. I will have to dig up the link. It’s just a lip mount I put on the access door.

 

I made my own mount that goes between the 3rd brake light and body. Works pretty good with a 1/4 wave. Definitely need a spring in the antenna in case you hit something.

 

Hahaha facts.

Ive gotten better. Mine rotates 90*. I've learned to pull it down when bushwacking and use the HT.

 

Yeah, I hit the antenna on the garage twice a day, everyday.

 

Today I finally slapped on my mag mount on the roof and connected it to my Baofeng. I have a Tram magnet and Browning Br180 antenna on it (bought on Amazon) and for now I ran the wire through rear window. I checked SWR with the meter I got for CB antenna tuning, and according to that it's 1.1 on 2 m and 1.4 on 70 cm (in not too perfect environment). I don't have a proper antenna analyzer so it is what it is (for now).
I seems to reach 2 of the usual repeaters from further distance and supposedly I don't sound chopped like I used to with HT rubber ducky. That Browning is not spring loaded, so I'll have to keep that in mind. I bought it a while ago and was planning on installing it on hood lip mount, but that idea has been scrapped due to possible radiation exposure (thank you TW, lol) when I'll eventually install my mobile rig. I really have a hard time finding time during decent weather to complete that project.

 

Well, this is certainly not accurate. db is a logarithmic scale, not linear. 3db is approximately double or half. 10db is 10x, 20db is 100x, 30 db is 1000x, etc.

 

I would love to find someone who made these for the Tacoma.

 

Since he said 20% power loss take per unit, 1 - 0.2 = 0.8 is power out. Therefore the ratio of power out / power in is 0.8.

10 * log (0.8) = -0.97 dB

10 * log (0.5) = -3 dB

10 * log (0.1) = -10 dB

I think the question is with respect to SWR, which is actually VSWR, voltage standing wave ratio. It's a measure of the voltage due to reflected power compared to the incident power. And ideal SWR is 1, meaning there is no reflected power (Gamma = 0) and the antenna radiated (or absorbs) all the power.



So if there's 20% power reflected due to mismatch, that's related to voltage by the square root of the power. So SQRT (0.2) = 0.45

VSWR = 1 + 0.45 / 1 - 0.45 = 2.636

So it would have to be really bad mismatch to lose 20% of your power.

Rearranging to find reflection coefficient from SWR.



Typically a SWR of 1.5 or so is good enough.

Reflection coefficient (gamma) = 1.5 - 1 / 1.5 + 1 = 0.2

Reflected power therefore is 100 * 0.2 ^2 = 100 * 0.04 = 4% or 10 * log (0.96) = 0.18 dB mismatch loss.

If your SWR is 2 your reflected power is 11%, 0.51 dB mismatch loss. A SWR of 3 is 25% reflected or 1.25 dB mismatch loss.