Stubby vs Whip

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Stubby vs Whip

Postby mes90265 » Sun Sep 25, 2011 6:37 pm

Hey Guys and Gals,


Just downgraded from my XTS5000. I now use an HT1000 16 channel UHF-H. I have a stubby antenna on it and the reception is complete sh*t. I ordered a whip and it should be here tuesday, but my question is: Will the whip make *that* much more of a difference in the coverage or is the radio just less sensitive then my previous? Any tips or tricks?
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Re: Stubby vs Whip

Postby Bill_G » Sun Sep 25, 2011 6:44 pm

The stubby was meant for public safety service with voting rcvrs and multiple transmitters, or in buildings with on site repeaters. It was compact, less prone to breakage, and didn't scrub your armpit when you sat down. It really wasn't meant for general purpose use. It was for close in coverage.
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Re: Stubby vs Whip

Postby mes90265 » Sun Sep 25, 2011 7:05 pm

so the whip should make a significant difference?
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Re: Stubby vs Whip

Postby MT2000 man » Sun Sep 25, 2011 7:13 pm

This topic has come up many times here before. The general consensus was that the whip DOES indeed perform better both TX and RX ( especially on simplex operations ) then the stubby.

BUT - to be perfactly honest, I run both the stubby and whips ( I change them out every so often ) on my XTS5000, and I don't really notice any difference at all. This is both with local repeater usage, AND simplex as well. ( This is all on UHF BTW).


I actually prefer the stubbies. They look much better on the radio IMO, get in the way less, and as I said, I have personally not found that much of a difference in performance.
Last edited by MT2000 man on Mon Sep 26, 2011 7:29 pm, edited 1 time in total.
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Re: Stubby vs Whip

Postby mr.syntrx » Mon Sep 26, 2011 12:16 am

I haven't noticed much of a performance difference either.

One thing to be keep in mind with the stubby is the reduced bandwidth compared with the whip. The whip is good across the whole UHF band but the stubby is useful for quite a bit less depending on what model you get, eg 440-470.
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Re: Stubby vs Whip

Postby Jim202 » Mon Sep 26, 2011 2:47 am

Unless you have a very well saturated coverage area, you will find the longer antenna will provide an increased performance. If you have the saturated coverage, which is rare today, swapping antennas won't make much difference.

You really need to get out on the edge of coverage and do your antenna swap testing there.

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Re: Stubby vs Whip

Postby Tom in D.C. » Mon Sep 26, 2011 7:55 am

At one time in my checkered career I took care of the radios for several sound system isntallation crews. The radios were GP300s and P110s, all on UHF. The overwhelming opinion of the antennas was that the full-sized, long, antennas were always better than the stubby antennas. Most comms were simplex inside buildings, floor-to-floor, etc. If you're working outside in the open on flat ground then the UHF stubby antenna is okay, otherwise I'd vote for the longer antenna every time. Keep in mind also that I'm talking about UHF, where the long antenna is an actual quarter-wave, or nearly so. On VHF you're liable to find that the differences between the two types are less noticeable, since the longer antenna is a helical coil and not a quarter-wave in the true sense.
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Re: Stubby vs Whip

Postby crazyboy » Mon Sep 26, 2011 5:31 pm

For me, it is the difference between making the repeater and not making it.
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Re: Stubby vs Whip

Postby GlennD » Mon Sep 26, 2011 7:06 pm

Ween we switched from Sabers to XTS5000s on UHF I set the radio in a vice so it would not move and set our remote controlled spectrum analyzer on Signal Hill to the channel under test. The full size XTS UHF antenna is not full size and I compared it to a stubby. Both antennas were checked within their ranges. On our 460 frequencies the measured signal was virtually the same.

This being the case, We ordered the radios with stubby antennas. We have a few officers that are on taskgroups that need City of LA freqs. Om those radios we use the longer whip since the stubby has a narrower band width.
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Re: Stubby vs Whip

Postby Jim202 » Tue Sep 27, 2011 3:44 am

GlennD wrote:Ween we switched from Sabers to XTS5000s on UHF I set the radio in a vice so it would not move and set our remote controlled spectrum analyzer on Signal Hill to the channel under test. The full size XTS UHF antenna is not full size and I compared it to a stubby. Both antennas were checked within their ranges. On our 460 frequencies the measured signal was virtually the same.

This being the case, We ordered the radios with stubby antennas. We have a few officers that are on taskgroups that need City of LA freqs. Om those radios we use the longer whip since the stubby has a narrower band width.


Have a question on where you placed the spectrum analyzer in relation to the radio. If you were in the near proximity of the radio, all measurements are invalid. You need to be away from the radio in the far field of the antenna. This would be some distance away from the radio. A good valid measurement would probably take a distance in the order of maybe a 1/4 mile.

You also said that you set the spectrum analyzer to the channel under test. On the 460 band using repeaters, your not very clear on weather you were looking at the output of a repeater or the input frequency that the portable was transmitting on. Hopefully you were looking at the portable radio TX frequency.

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Re: Stubby vs Whip

Postby GlennD » Tue Sep 27, 2011 6:22 am

The spectrum analyzer was located at Signal Hill (around 350ft) about 5 miles away and of course we were looking at the input. We have several remote spectrum analyzers. They are very helpful for locating interference. They are connected to the receiver multicouplers so the transmitters are filtered out but that restricts the tuning range.
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Re: Stubby vs Whip

Postby mes90265 » Tue Sep 27, 2011 12:34 pm

Hey Glenn. I am in LACO and I have an HT1000 as stated, everything around here is UHF as you know and so I just thought I would use my old XTS5000 stubby for it... However, It seems as if reception is spotty, just about everywhere with the little guy. The whip comes in tomorrow and we will see if that cures all. I have LASD, LACOFD, LBPD, and Samo fire programmed in as well as the saddle peak GMRS site. This is frustrating but I am hoping the whip will be the cure. If not, I will need to return the radio :/
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Re: Stubby vs Whip

Postby g8tzl2004 » Tue Sep 27, 2011 3:55 pm

I have several UHF Jedi portable radios like the HT1000 (same RF board). I have found that there is a big variation in receive sensitivity between identical radios. They are all within the very pessimistic minimum spec (around 0.3uV 117dBm) but some are much more sensitive ie.around 0.14uV 124dBm - which is an enormous 7dB difference.

With portable UHF Jedi's, it appears to be the luck of the draw whether you get a sensitive one!!! I have also noticed that many of the UHF Jedi's have drifted over 1KHz off frequency. If the radio is +1Khz off and the repeater is -1Khz off, the overall error is 2Khz which can effect sensitivity.

I have found that VHF Jedi portables are more consistant - as are the Jedi mobile radios. I don't know why the UHF Jedi's are so variable as far as receive sensitivity is concerned..maybe something to do with component tolerances.
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Re: Stubby vs Whip

Postby Jim202 » Wed Sep 28, 2011 4:05 am

g8tzl2004 wrote:I have several UHF Jedi portable radios like the HT1000 (same RF board). I have found that there is a big variation in receive sensitivity between identical radios. They are all within the very pessimistic minimum spec (around 0.3uV 117dBm) but some are much more sensitive ie.around 0.14uV 124dBm - which is an enormous 7dB difference.

With portable UHF Jedi's, it appears to be the luck of the draw whether you get a sensitive one!!! I have also noticed that many of the UHF Jedi's have drifted over 1KHz off frequency. If the radio is +1Khz off and the repeater is -1Khz off, the overall error is 2Khz which can effect sensitivity.

I have found that VHF Jedi portables are more consistant - as are the Jedi mobile radios. I don't know why the UHF Jedi's are so variable as far as receive sensitivity is concerned..maybe something to do with component tolerances.


Sounds like it is time to bench the radios and go through a full service alignment on them. Using a radio that is 1 KHz off frequency is like asking for it not to work. The sensitivity will be effected and probably the ability to have someone hear you out on the edges of the system coverage will be effected also.

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Re: Stubby vs Whip

Postby g8tzl2004 » Wed Sep 28, 2011 7:58 am

I have found that identical UHF Jedi's which are carefully aligned (front end and ref osc) can have a significant difference in sensitivity.

In the archive there are some interesting comments from Karfield who found that sensitivity of a fully aligned Jedi (like a HT1000) can range from 0.38uV to 0.2uV....which is an enormous difference....although all radios are still in spec. My best UHF Jedi has sensivity around 0.14uV which is really hot while some of my other "identical" Jedi's are a bit deaf...around 0.28uV. All my VHF Jedi' have excellent sensitvity. Its just the UHF Jedi's which are very variable...even with a carefully aligned radio...so its the luck of the draw whether you get a good one!!

If you have a deaf Jedi, then the gain difference between a stubby and a whip will not be able to offset a deaf front end. You will need something like a 6 element beam rather than a 6 inch whip !!!!
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Re: Stubby vs Whip

Postby MT2000 man » Wed Sep 28, 2011 9:34 am

It would still be interesting to know (for haha's) what band you are all using, along with the radio, and antenna along with coverage area. I'll almost guarantee that most of us run the full length whip regardless of what band / radio, but would still be interesting to know. I'll start :

UHF XTS5000 w/ whip antenna mixed (local repeaters, some simplex) operations.
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Re: Stubby vs Whip

Postby N4KVE » Wed Sep 28, 2011 2:04 pm

Flying by the seat of my pants with no test equipment, I go to the pool about 1/2 mile away from my house using the same 2 UHF Jedi's talking to my GF on simplex. With factory whip, 95% or better. Using factory stubby, 80%, so it's almost as good, but not quite. However, on 900 MHZ using the factory whip, it's 90%, but with the factory stubby on both radios, it's 50%. Big difference between UHF, & 900. GARY N4KVE
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Re: Stubby vs Whip

Postby MT2000 man » Wed Sep 28, 2011 6:06 pm

Also speaking of antennas, has anyone tried / noticed better performance with the GPS / APX (the TRBO looking antennas) antennas on the XTS series of radios ?
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