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LOW BAND: Which freq is better?

Posted: Tue Jan 10, 2006 7:50 pm
by w8cmi
I'm working with a customer in a rural, hilly area who wants basic base to mobile communication. I'm looking at low band and am wondering if other techs have good or bad experiences with certain ranges of frequencies in the low band range.

I'm looking at:

The 30-31 MHs business channels
The 35 MHz business channels
The 43-44 MHz (old) motor carrier channels
The 48-49 MHz power/petroleum/forest products channels

There's plenty of stuff available, at least according to the FCC website, so *getting* a channel from the coordinator shouldn't be a problem. I'm looking at a 50-60' tower on a hilltop, with 100 watts RF into a DB201 folded dipole (the best low band base antenna available, IMHO!) and probably 60 or 100 watt mobiles.

PL is an absolute must and will be included. I don't do carrier squelch anything. :wink:

Has anyone seen better range or less interference on one range of frequencies vs. the others? Any other technical issues I should be aware of? It's been a while since I built a low band system from scratch.

RICK 8)

Posted: Tue Jan 10, 2006 8:30 pm
by Max-trac
The lower freqs are more prone to interference from "skip" propogation.
IE the 29 meg Ham band has a LOT more skip than the 52 meg band...

Posted: Tue Jan 10, 2006 10:49 pm
by jim
I'm partial to the sub-35 frequencies.
If you can get licensed for more power, do it. You never know when you'll run into an old 500 watt GE transmitter!

Lowband forever!

Posted: Wed Jan 11, 2006 5:27 am
by firetech792
Also, I would go with a DPL.........it will lessen the chance of skip comming through on a duplicated standard PL.

Posted: Wed Jan 11, 2006 6:11 am
by kb3jkp
no,no,no


motorola wants you to go to a smartzone Omnilink 800 Mhz Trunking system.....

with XTL-5000 mobiles, with VRS, and UHF XTS5000's for the VRS links.. all IMBE ...oh..excuse me.. "ASTRO"......

you might have to build like...40 or so towers.....but.. lowband is old technology.. you need the "all new and improved" Astro..... which gives you better range and better voice quality...........



lol


OK.. I just love doing that.....


LB still kicks A........

I think some GE orions or some X9000's would do the trick nicely.. I personally would choose the lower 30's,with PL...... I think DPL would close too quickly.....in a "scratchy" situation....... use a "non-standard" PL ....

the X9000's are inexpensive, put out 110W+ and can cover the 27-54 Mhz split in ONE radio(although good luck getting an antenna to cover that), so if, in the future, you move to different frequencies, there's no need to get another mobile(orions come in 2 LB splits)....although "old" and discontinued, the X9000 is a workhorse.. and I will hold onto mine......until everyone stops using lowband......(and 6m and 10m FM are dead)

Posted: Wed Jan 11, 2006 8:40 am
by illini52
Cooooooool. Someone who wants to use lowband.
About the only ones left on LB in Illinois are the State Police. They have pretty good luck in the 42 meg range. I'd say you are safe with any of the freq ranges, but I'd stay above 35 megs IMO.

Posted: Wed Jan 11, 2006 9:15 am
by apco25
Its not the band so much as the antenna. You'll need a good antenna with a good ground.

Low band antenna performance is critical due to ground plane size and shape.

I'd go higher if possible as it does shorten the antenna length some especially if you use a real man's antenna - the ball mount with spring.

You'll be close to CB length whip on the low 30 Mhz freqs.

Go with the Orion over the X9000. I love the X9000. Great radio, but its huge by today's standards. 110w Orions are smaller than a 110w spectra tray.

Posted: Wed Jan 11, 2006 3:33 pm
by KitN1MCC
i would go with the 40 MHZ section and use a the good old Ball and Whip mount

Not that many Business are still on low band easy to get a channel

Posted: Wed Jan 11, 2006 10:49 pm
by jim
Let's not forget about the 30 series Kenwoods!

Drive a 1KW mobile amp and feed it into a ball mount and you'll be in good shape across 7 states.

Posted: Thu Jan 12, 2006 2:37 pm
by LAC-OPS
I don't know if this is going to happen in your area, but the BPL (Broadband over power lines) that is being released is supposed to wreak havoc for lowband users. I've heard it's especially bad in the lower portion of the band.

Just something to think about.. maybe the 48 meg side would be a better choice.

Low Band

Posted: Thu Jan 12, 2006 7:16 pm
by greenline
We use low band for our Agency , Pa Game Commission. 44-45 range. Works pretty good here and we have lots of mountains.
ERS

Posted: Thu Jan 12, 2006 7:18 pm
by apco25
No OpenSky for the CO's?

Posted: Fri Jan 13, 2006 6:18 am
by jim
Open Sky makes the Motorola ASStro 800/P25 system actually look good. Maybe, just maybe someday the PSP system will work.

A really screwed up, out of freq fading signal from an old tube amp lowband is still sounds better then anything digitial. And it's interoperable!