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Posted
1 hour ago, gman1971 said:

Well, testing MURS vs FRS range with CCRs is like testing how accurate an AR-15 would be by using an airsoft replica... 

All those radios have nearly equal, or equally poor dynamic sensitivity, measured around -90 dBm, in both V/U bands. The Gen1 XPR 6550 has about -110 dBm dynamic sensitivity, so if you want to test MURS vs FRS, get a pair of 6550, one U, one V, and run the test with genuine Motorola VHF/UHF antennas, and while at it measure the RSSI too. Gives you real data, rather than "can you hear me now", which is so "reliable" and reminds me of an old TV commercial for cell phone coverage, when coverage used to be poor at best... just like CCR range.

G.

I agree.

Any test would need to remove as much of the variability due to hardware differences. Some of the Motorola radios have a RSSI indicator feature. I looked at a video where a 7550 was being compared to the 7750e model. Nice feature when you need it. I’m assuming the RSSI reading levels are accurately calibrated.

I have both the VHF and UHF models of the XPR-6550’s. I haven’t done anything with them in a while. I have to check and see if they have a displayable RSSI. If they do the second item to consider are they calibrated. Being purchased used I wouldn’t be so sure. Some of the radios didn’t come with antennas so I had to get some aftermarket ones. That’s the other unknown.

I had to purchase the antennas since the Kenwood ones won’t work, including the cheap Chinese radio ones. They screw on OK, SMA socket. However the center pin is recessed deeper in the socket on the radio. The pin won’t mate with the center hole on the antenna. The typical reverse SMA antenna the center contact is recessed while the Motorola is flush. They just had to be different, likely done for marketing reasons. Because of this I had to be careful which ones I purchased as generic replacements.

Since we’re dealing with FM the important parameter is received signal strength. Radios need a minimum signal strength above the noise floor for an acceptable level of communication quality.

Posted
On 12/7/2021 at 3:17 PM, kb2ztx said:

My 1 watt HT1000 talks further than a FRS radio time and tome again. Love to have 5 watts to use but for what I use it for 1 watt is perfect. 

 

At my Ham radio coffee group meet tonight one of the guys brought in some Motorola radios. He wanted to know if one of the other guys could program them. One was the HT-1000. That was a rather large radio.

Posted
11 minutes ago, Lscott said:

Some of the radios didn’t come with antennas so I had to get some aftermarket ones. That’s the other unknown.

I had to purchase the antennas since the Kenwood ones won’t work, including the cheap Chinese radio ones. They screw on OK, SMA socket. However the center pin is recessed deeper in the socket on the radio. The pin won’t mate with the center hole on the antenna. The typical reverse SMA antenna the center contact is recessed while the Motorola is flush.

Quality two way radios has been my source for good antennas for my Vertex stuff...a couple of my came with pretty beat up antennas. one, the little screw on bushing had come loose from the bottom of the antenna (sma-m on the antenna, sma-f on the radio). I've also seen batches of supposedly factory moto antennas on ebay (packs of 10 or more) for not crazy prices too.

https://quality2wayradios.com/store/two-way-radio-accessories/antennas-handheld-radios/vertex-standard-antennas

My evx seem to get along okay  with other antennas if I use an adapter screwed in, and attach the antenna to that, though that kind of defeats some of its water resistance.

Posted
4 hours ago, Lscott said:

I agree.

Any test would need to remove as much of the variability due to hardware differences. Some of the Motorola radios have a RSSI indicator feature. I looked at a video where a 7550 was being compared to the 7750e model. Nice feature when you need it. I’m assuming the RSSI reading levels are accurately calibrated.

I have both the VHF and UHF models of the XPR-6550’s. I haven’t done anything with them in a while. I have to check and see if they have a displayable RSSI. If they do the second item to consider are they calibrated. Being purchased used I wouldn’t be so sure. Some of the radios didn’t come with antennas so I had to get some aftermarket ones. That’s the other unknown.

I had to purchase the antennas since the Kenwood ones won’t work, including the cheap Chinese radio ones. They screw on OK, SMA socket. However the center pin is recessed deeper in the socket on the radio. The pin won’t mate with the center hole on the antenna. The typical reverse SMA antenna the center contact is recessed while the Motorola is flush. They just had to be different, likely done for marketing reasons. Because of this I had to be careful which ones I purchased as generic replacements.

Since we’re dealing with FM the important parameter is received signal strength. Radios need a minimum signal strength above the noise floor for an acceptable level of communication quality.

Yes, the 6550 has an RSSI meter (button left left left, button right right right). Most of them are very well calibrated, and out of all the XPR radios I've purchased in the past 2 years only one was wrong...

Well, if you value weak signal work, and are not blessed with a great site to place your base antenna, then I think the XPR 7550e havaing a 4 dB improvement in digital receiver performance (-0.14uV 5% BER, with amazing selectivity to boot, and better FM sens too, 0.16 12SINAD IIRC) is the radio to chose. Also, the e model has a battery life of 30+ hours, along with WiFi and BT4.0 and some other improvements which I don't remember at the top of my head. Like I said, I went with e b/c the additional sensitivity.

The RSSI meter has been an invaluable tool in my quest to go from <1 mile range to 20+ miles range, before that it was all a guess game, no more. Now I have many spreadsheets with precise data of what does what, and how different components affect range, the ultimate goal in radio...  .... so, yes having reliable RSSI measurements of the noise floor is so very important. Noise floor measurements tells you if your radio is actually reached its max receiver potential, or if the noise floor is preventing you from listening to the signals. For example I know that around here, in Madison WI, there are traffic intersections that are absolutely atrocious in terms of RFI noise, with a whopping RSSI of 80s dBm noise floor! Its basically a dead spot, no VHF gets through, at all, you drive 5 yards out of the intersection and noise floor drops back to -118 dBm... Noise floor also tells you if a radio has poor dynamic sensitivity, as those can be used to sort of pseudo ISO-tee with other radios... etc.

G.

Posted
4 hours ago, wayoverthere said:

Quality two way radios has been my source for good antennas for my Vertex stuff...a couple of my came with pretty beat up antennas. one, the little screw on bushing had come loose from the bottom of the antenna (sma-m on the antenna, sma-f on the radio). I've also seen batches of supposedly factory moto antennas on ebay (packs of 10 or more) for not crazy prices too.

https://quality2wayradios.com/store/two-way-radio-accessories/antennas-handheld-radios/vertex-standard-antennas

My evx seem to get along okay  with other antennas if I use an adapter screwed in, and attach the antenna to that, though that kind of defeats some of its water resistance.

Those in a pack are not real Motorola antennas. IMO, buy directly from MOL, I buy all my XPR antennas from MOL directly, as giving money to the counterfeiters only makes the problem worse.

Those counterfeit SMA antennas are much worse than the genuine Motorola antennas I've purchased directly from MOL, as measured with multiple antenna analyzers.

Also, to be clear, most "official Motorola dealers" on eBay price gouge the heck out of you, and most are lazy that take a week to ship stuff out.... My experience with MOL has been pretty much great, I know, some people have had some horror stories, but not my case... and most antennas I've purchased directly from MOL took <48 hours to show up at my doorstep, at a lower price tag.

G.

Posted

There are no 800 mhz free services for non-ham operators. If you want a license free 900MHz radio get a Motorola DTR, its a 1W FHSS radio that will destroy every CCR in the market for short range reliable, and secure comms.

G.

Posted
4 hours ago, Lscott said:

HT1000 is a pretty decent radio. Don't be fooled by the specs in the receiver sensitivity, as the HT1000 VHF model has a pretty darn hot receiver... which also has selectivity to boot too... the claimed specs are -118 dBm (0.28 uV @ 50ohm) 

Personally I would go with the HT1250/HT1550... with the full keypad... but... that's just me.

G.

Posted
10 minutes ago, gman1971 said:

Those in a pack are not real Motorola antennas. IMO, buy directly from MOL, I buy all my XPR antennas from MOL directly, as giving money to the counterfeiters only makes the problem worse.

Those counterfeit SMA antennas are much worse than the genuine Motorola antennas I've purchased directly from MOL, as measured with multiple antenna analyzers.

Also, to be clear, most "official Motorola dealers" on eBay price gouge the heck out of you, and most are lazy that take a week to ship stuff out.... My experience with MOL has been pretty much great, I know, some people have had some horror stories, but not my case... and most antennas I've purchased directly from MOL took <48 hours to show up at my doorstep, at a lower price tag.

G.

Yeah, that's why i included "supposedly" and didn't link any ? I don't always trust ebay, and you don't even have the relatively easy return policies backing you like Amazon (which has its own counterfeit issues. And especially little stuff like that that would be easy to fake, and I don't have a need for that many. when there's not much difference between an authorized dealer and ebay, it's worth  a couple extra bucks or so to go to a source more likely to be reputable and selling genuine products.

Posted
1 hour ago, gman1971 said:

HT1000 is a pretty decent radio. Don't be fooled by the specs in the receiver sensitivity, as the HT1000 VHF model has a pretty darn hot receiver... which also has selectivity to boot too... the claimed specs are -118 dBm (0.28 uV @ 50ohm) 

Personally I would go with the HT1250/HT1550... with the full keypad... but... that's just me.

G.

Thats why we still carry them for SAR. They are simple radios and just work. 

Posted
2 hours ago, gman1971 said:

Those in a pack are not real Motorola antennas. IMO, buy directly from MOL, I buy all my XPR antennas from MOL directly, as giving money to the counterfeiters only makes the problem worse.

Those counterfeit SMA antennas are much worse than the genuine Motorola antennas I've purchased directly from MOL, as measured with multiple antenna analyzers.

Also, to be clear, most "official Motorola dealers" on eBay price gouge the heck out of you, and most are lazy that take a week to ship stuff out.... My experience with MOL has been pretty much great, I know, some people have had some horror stories, but not my case... and most antennas I've purchased directly from MOL took <48 hours to show up at my doorstep, at a lower price tag.

G.

Yep, brand new antennas on my Vertex HTs from MOL for about $1 cheaper than the ebay special, and got to my door much quicker.

Posted
10 hours ago, gman1971 said:

Those counterfeit SMA antennas are much worse than the genuine Motorola antennas I've purchased directly from MOL, as measured with multiple antenna analyzers.

I've tried testing a handful of HT antennas. They are hard to test. Hold it a bit different and the results change all over the place. Get one that tests crappy then move it around or change the test fixture a bit and bang, it now looks better than the one you thought was the best one in the batch. I've had some that look bad using a ground plane and much better without. Then there are those other ones that do the exact opposite. Go figure.

A fair test would duplicate the exact installation conditions in a test fixture as it would see installed on a radio. That's almost impossible to do unless you want to rip out the guts out of a junk radio to add in a cable wired to the socket and run to the analyzer. Then you have to get a calibrated hand and arm to hold it and hope you can replicate the setup from one test to the next. I would like to see how the manufactures do this.

Posted
15 hours ago, Lscott said:

I've tried testing a handful of HT antennas. They are hard to test. Hold it a bit different and the results change all over the place. Get one that tests crappy then move it around or change the test fixture a bit and bang, it now looks better than the one you thought was the best one in the batch. I've had some that look bad using a ground plane and much better without. Then there are those other ones that do the exact opposite. Go figure.

A fair test would duplicate the exact installation conditions in a test fixture as it would see installed on a radio. That's almost impossible to do unless you want to rip out the guts out of a junk radio to add in a cable wired to the socket and run to the analyzer. Then you have to get a calibrated hand and arm to hold it and hope you can replicate the setup from one test to the next. I would like to see how the manufactures do this.

RSSI meter usually corroborates the tester results, difference can be greater than 10 dB sometimes, sometimes is not that obvious but the radio tends to perform worse at long range, etc....

IMO, the rubber duck antenna is already a compromise, so why would anyone save a few bucks (if that) on a knocoff, which could potentially have even less performance... well, I guess CCRs are being bought left and right, so performance is not a priority, ... moot point. Oh well... 

G.

Posted
On 12/10/2021 at 3:18 AM, gman1971 said:

Yes, the 6550 has an RSSI meter (button left left left, button right right right). Most of them are very well calibrated, and out of all the XPR radios I've purchased in the past 2 years only one was wrong...

Well, if you value weak signal work, and are not blessed with a great site to place your base antenna, then I think the XPR 7550e havaing a 4 dB improvement in digital receiver performance (-0.14uV 5% BER, with amazing selectivity to boot, and better FM sens too, 0.16 12SINAD IIRC) is the radio to chose. Also, the e model has a battery life of 30+ hours, along with WiFi and BT4.0 and some other improvements which I don't remember at the top of my head. Like I said, I went with e b/c the additional sensitivity.

The RSSI meter has been an invaluable tool in my quest to go from <1 mile range to 20+ miles range, before that it was all a guess game, no more. Now I have many spreadsheets with precise data of what does what, and how different components affect range, the ultimate goal in radio...  .... so, yes having reliable RSSI measurements of the noise floor is so very important. Noise floor measurements tells you if your radio is actually reached its max receiver potential, or if the noise floor is preventing you from listening to the signals. For example I know that around here, in Madison WI, there are traffic intersections that are absolutely atrocious in terms of RFI noise, with a whopping RSSI of 80s dBm noise floor! Its basically a dead spot, no VHF gets through, at all, you drive 5 yards out of the intersection and noise floor drops back to -118 dBm... Noise floor also tells you if a radio has poor dynamic sensitivity, as those can be used to sort of pseudo ISO-tee with other radios... etc.

G.

I've been quite impressed with with RF performance of the 7550e I carry for work. It maintains control channel reception even several floors underground. Motorola's engineers did good work with the Rodinia receiver.

I personally haven't seen 30-hour battery life. On an LCP system with midlife batteries, we get 9-15 hours per charge.

My personal "weapon of choice" is an EFJ 5100ES. I've always liked P25 audio a bit more than DMR, and the controls are very glove-friendly (especially with 51FIRE blade knobs). Specified sensitivity is only 0.25uV and I haven't hooked one up to a monitor to see how actual performance compares to the spec. I guess I give up some performance to get PS-grade controls at that price, but with proper end user training and employment it's not been noticeable.

I use two antennas, a Smiley Super Stick and an RCBI stubby. The stubby is for MMDVM hotspot use and underground work where a whip would get snagged. When handheld or worn on a chest rig/harness, that Smiley gets out better than anything I've ever used. It's surprisingly close to mobile performance.

Posted
7 hours ago, DeoVindice said:

I've been quite impressed with with RF performance of the 7550e I carry for work. It maintains control channel reception even several floors underground. Motorola's engineers did good work with the Rodinia receiver.

I personally haven't seen 30-hour battery life. On an LCP system with midlife batteries, we get 9-15 hours per charge.

My personal "weapon of choice" is an EFJ 5100ES. I've always liked P25 audio a bit more than DMR, and the controls are very glove-friendly (especially with 51FIRE blade knobs). Specified sensitivity is only 0.25uV and I haven't hooked one up to a monitor to see how actual performance compares to the spec. I guess I give up some performance to get PS-grade controls at that price, but with proper end user training and employment it's not been noticeable.

I use two antennas, a Smiley Super Stick and an RCBI stubby. The stubby is for MMDVM hotspot use and underground work where a whip would get snagged. When handheld or worn on a chest rig/harness, that Smiley gets out better than anything I've ever used. It's surprisingly close to mobile performance.

Have mostly used Motorola hardware for GMRS, along with my recent GM-30 and Radioddity DB20-G mobile, but may dust off some of my old EFJ radios that have been stored away......parting gifts from my time at Zetron, then a part of the JVC/Kenwood Group. Have heard many people state they prefer the EFJ mobiles, but have yet to use mine for anything in several years. Thank you for posting.

Posted
9 hours ago, DeoVindice said:

I've been quite impressed with with RF performance of the 7550e I carry for work. It maintains control channel reception even several floors underground. Motorola's engineers did good work with the Rodinia receiver.

I personally haven't seen 30-hour battery life. On an LCP system with midlife batteries, we get 9-15 hours per charge.

My personal "weapon of choice" is an EFJ 5100ES. I've always liked P25 audio a bit more than DMR, and the controls are very glove-friendly (especially with 51FIRE blade knobs). Specified sensitivity is only 0.25uV and I haven't hooked one up to a monitor to see how actual performance compares to the spec. I guess I give up some performance to get PS-grade controls at that price, but with proper end user training and employment it's not been noticeable.

I use two antennas, a Smiley Super Stick and an RCBI stubby. The stubby is for MMDVM hotspot use and underground work where a whip would get snagged. When handheld or worn on a chest rig/harness, that Smiley gets out better than anything I've ever used. It's surprisingly close to mobile performance.

I concur. The 7550e receiver is pretty darn nice...

I've seen 30 hours on 3000 mAh packs when mostly in standby. If you start using the radio it drops to the very high 20 hours of use on 3000 packs.

G.

Posted
16 hours ago, gman1971 said:

RSSI meter usually corroborates the tester results, difference can be greater than 10 dB sometimes, sometimes is not that obvious but the radio tends to perform worse at long range, etc....

IMO, the rubber duck antenna is already a compromise, so why would anyone save a few bucks (if that) on a knocoff, which could potentially have even less performance... well, I guess CCRs are being bought left and right, so performance is not a priority, ... moot point. Oh well... 

G.

I’m going to have to try it out on the XPR-6550’s. I see people claim brand “X” antenna works better than brand “Y” because they can get in to a distance repeater. That’s sort of hard to really qualify without measured data.

Posted
48 minutes ago, Lscott said:

I’m going to have to try it out on the XPR-6550’s. I see people claim brand “X” antenna works better than brand “Y” because they can get in to a distance repeater. That’s sort of hard to really qualify without measured data.

Yep, pretty much anything that is tested using a good quality repeater is doomed to succeed; in fact, I would venture to say that you can probably hit a local repeater with a dummy load on the SMA antenna port... :D 

G.

Posted
1 hour ago, gman1971 said:

Yep, pretty much anything that is tested using a good quality repeater is doomed to succeed; in fact, I would venture to say that you can probably hit a local repeater with a dummy load on the SMA antenna port... :D 

G.

I was testing a sma adapter the other day on one of the evx-539's, while listening to the local public safety frequency.  I went to swap antennas while they were talking, and realized i could still hear the dispatcher, albeit with a bit of static, with no antenna at all. Tried touching my finger to the center pin in the SMA port and it was crystal clear.  Don't know what kind of swr i'd present if i tried to transmit through my finger, though.

Posted
1 hour ago, wayoverthere said:

I was testing a sma adapter the other day on one of the evx-539's, while listening to the local public safety frequency.  I went to swap antennas while they were talking, and realized i could still hear the dispatcher, albeit with a bit of static, with no antenna at all. Tried touching my finger to the center pin in the SMA port and it was crystal clear.  Don't know what kind of swr i'd present if i tried to transmit through my finger, though.

Probably 40-50 dB attenuation. On a 6550 you can find out, via RSSI meter... I just don't remember at the top of my head, but on the 7550e the attenuation is quite low, since its not an SMA port..

Posted
Yep, pretty much anything that is tested using a good quality repeater is doomed to succeed; in fact, I would venture to say that you can probably hit a local repeater with a dummy load on the SMA antenna port...  
G.

Funny you said that. Earlier this year I did some local testing that involved use of a dummy load on radio with 1/2 watt. Signal was receivable 1/3-1/2 mile away.


Michael
WRHS965
KE8PLM
Posted
14 minutes ago, mbrun said:


Funny you said that. Earlier this year I did some local testing that involved use of a dummy load on radio with 1/2 watt. Signal was receivable 1/3-1/2 mile away.


Michael
WRHS965
KE8PLM

Yep, I believe it... I use a dummy load for the primary reflector, so the range is only about 1/5th of a mile, enough to cover all the offices/rooms, but useless for anyone else trying to bootleg it, unless of course, they are inside the premises... 

G.

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