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Which digital voice mode do you prefer?


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On 9/4/2021 at 2:57 PM, gman1971 said:

WRNA236,

Respectfully, none of those points put the XPR as bad as you want them to be. The XPR7550e has the best digital receiver I've tested in a radio, and analog performance is about as good as the best APXs radios as well. Oh, and lets not forget the APX900 is basically a rebadged XPR7550e, so your statement is completely unfounded and thus, purely your own opinion, and we all have an opinion.

The enhanced noise suppressor option on these XPR gen2 radios is pretty darn good. In the end, what mattered to me was the receiver performance, which is pretty darn good on those XPR gen2.5 radios. The only feature that only two APX radios have (7k 8k, aside from the useless-to-me body ratings, IP ratings, UL, etc) was having multiband capability, but at 10x cost price hike, I made the decision to stay with XPR radios, b/c the receiver fits the bill to what I need.

So, we are now comparing body ratings too? Lets see..., ah yes, why do I care? I really don't. These XPR radios have survived everything we've thrown at them in day to day operations, and then nature during hikes, water, snow, dirt. Sure, you can argue the screen is cheap plastic, etc, and not gorilla glass... etc... but let me reiterate this again: the only two APX radios I would even consider as an upgrade to my XPR7550e are the APX 7000 and/or 8000, which are 10x the price of a used XPR radio and I am not willing to pay that.  Certainly not for a feature that I've proved (to me) that I didn't really need as everyone tried to mislead me that I needed, (now, that is not the same as I wouldn't mind having it, should it be available)

And back on topic, this is a digital modulation preference thread, not an APX vs XPR bash.

G.

I'll vouch for the durability of the XPR7550e. I carry one as my work radio and it's gone through some pretty awful abuse with nary an issue. I really couldn't ask for better durability, the thing has been doused with abrasive slurry, blasted with high-pressure hoses, banged around on vehicles and equipment, and subjected to high in-vehicle temperatures for days on end. As much as I criticize MSI, they still have engineers who can design a great hardware package (other than overly-sensitive PTTs and channel knobs).

Audio quality is another matter entirely. It completely falls apart to the point of unintelligibility in high-noise environments even with noise suppression enabled. Generally, P25 radios are built with fire service in mind and have better noise cancellation than other offerings, which is a point in favor of P25 in my opinion. A 5100ES blows a 7550e away when used next to a filter press or non-muffled air-cooled diesel engine at full throttle.

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15 hours ago, tweiss3 said:

The NX-5000 are capable of all three digital modes, but can only do two at a time.

If I got one for free I’m not complaining. Maybe some future update might eliminate that restriction. Likely the two that I would use are DMR and P25. The radios are very expensive and the software requires registration with license files etc. For a business they can deal with it. For a private individual for hobby use, not going to happen, not me anyway.

I have a used XPR6550 VHF radio I just purchased for $75 off my favorite auction site coming.  

I have a used XPR6580 for $45 that should be shipping in a day or two. There is reportedly a way to put it on the Ham 33cm band. That’s why I was interested

Unfortunately it seems I need the conventional version of the firmware. The radio looks like it has the trunking firmware which I’m lead to believe won’t work with the code plug hack to put the radio on 33cm. Until I can scam up the right firmware the radio will go into a storage box.

I would also like to get my hands on the current version of the XPR6550 firmware for the VHF/UHF radios.

Now that I seem to have a functioning version of the Motorola Mototrbo software I going to experiment with a few of them.

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3 hours ago, DeoVindice said:

I'll vouch for the durability of the XPR7550e.

Does anybody use one with an external antenna? It seems Motorola took a good radio and sort of mucked it up by using that funky stud type antenna connector.

Looking at some videos, showing a stud to BNC adapter, a thin copper foil ground strap is required to be run from the inside edge of the antenna well, over the top rear edge of the radio down to the mounting screw for the belt clip. That screw is in the aluminum chassis providing the ground connection for the adapter. When the adapter is screwed in the “shell” makes contact with the copper foil ground strap completing the coax shield connection to the ground side of the radio. This doesn’t require any permanent modifications to the radio or interferes with the normal use of the rubber duck antenna.

I really don’t like this since the length of copper foil from the antenna well to the grounding screw likely results in a significant impedance bump. However without it the coax just turns in to one long grossly mistuned antenna.

At least with the older XPR6550’s I’m going to experiment with they use fairly standard SMA antenna sockets on the radios. I have a bunch of SMA male and SMA female to BNC adapters I can use.

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The 7550 uses a specific antenna adapter sold by motorola. Its not cheap. 99% of the market uses the rubber duck. People forget B&I doesn't use external antenna's on a portable. They use a mobile radio. Radio isn't marketed to ham and GMRS users so real no need to have it. I agree a SMA would have been nice, but engineers have reasons. 

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8 hours ago, Lscott said:

Does anybody use one with an external antenna? It seems Motorola took a good radio and sort of mucked it up by using that funky stud type antenna connector.

Looking at some videos, showing a stud to BNC adapter, a thin copper foil ground strap is required to be run from the inside edge of the antenna well, over the top rear edge of the radio down to the mounting screw for the belt clip. That screw is in the aluminum chassis providing the ground connection for the adapter. When the adapter is screwed in the “shell” makes contact with the copper foil ground strap completing the coax shield connection to the ground side of the radio. This doesn’t require any permanent modifications to the radio or interferes with the normal use of the rubber duck antenna.

I really don’t like this since the length of copper foil from the antenna well to the grounding screw likely results in a significant impedance bump. However without it the coax just turns in to one long grossly mistuned antenna.

At least with the older XPR6550’s I’m going to experiment with they use fairly standard SMA antenna sockets on the radios. I have a bunch of SMA male and SMA female to BNC adapters I can use.

No, I just use the OEM whip antenna. I might swap it out for a stubby to keep it from getting snagged as much, this is a short-range Capacity Plus system and squeezing out every last drop of portable performance just isn't necessary.

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2 hours ago, kb2ztx said:

The 7550 uses a specific antenna adapter sold by motorola. Its not cheap. 99% of the market uses the rubber duck. People forget B&I doesn't use external antenna's on a portable. They use a mobile radio. Radio isn't marketed to ham and GMRS users so real no need to have it. I agree a SMA would have been nice, but engineers have reasons. 

Trust me, I’m an engineer too, doing R and D new product design, and sometimes stupid crap gets done because of a mandate by marketing and upper management. They want special tweaks that lock in customers where they have to buy parts and service from us. Not everything is for well reasoned design decisions.

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4 hours ago, Lscott said:

Trust me, I’m an engineer too, doing R and D new product design, and sometimes stupid crap gets done because of a mandate by marketing and upper management. They want special tweaks that lock in customers where they have to buy parts and service from us. Not everything is for well reasoned design decisions.

Lscott, there is no adapter AFAIK. There is a callbox option that is basically a 7550e with an SMA connector. Get that if you really want SMA on your 7550e.

Personally, the stud antenna has worked well enough for me; and sure, it would've been nice to have had an SMA, but the radio is solid and it works very well as is. Given the amount of POS antennas sold today, I am somewhat glad that those antennas are <10 bucks from Motorola Solutions directly, so I know my antennas are not some knock-off crap. 

And I used to use my 6550s (and other radios before that) as low power portables... but after trying a 5550e with a sweet HHCH, with 20+ miles simplex, I am never going back to these days.

Then, if you really needed longer range than that, for a SHTF situation, you should probably invest on a Yaesu Vertex FD-817 for long range comms, and not use GMRS, or VHF, including any digital modulation for that matter. A good 817 atop a high hill, or a tall mount, will probably open the entire world for comms, certainly reaching further than a 6550, 7550e, 5550e, or even the "luxury transceiver" APXs would ever dream of reaching with or without an SMA port. 

G.

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Yep, upper management and marketing have to have their say, always, and there really isn't much you can do about that.

With that said, I am pretty certain the engineers who designed the 7550e weren't thrilled with the stud on their masterpiece, but hey, people have bills to pay, and they wanted to keep their job, so you do what you have to do.

G.

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And yet the same XPR7550e radio sold over in the EU as a DP4801 can be ordered up with an SMA connector (as a regular radio option, no call box option needed).

I think it's all marketing. Nothing to do with the engineers. Same reason why Motorola won't give their APX series radios DMR capability.

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5 hours ago, gman1971 said:

Lscott, there is no adapter AFAIK. There is a callbox option that is basically a 7550e with an SMA connector. Get that if you really want SMA on your 7550e.

Personally, the stud antenna has worked well enough for me; and sure, it would've been nice to have had an SMA, but the radio is solid and it works very well as is. Given the amount of POS antennas sold today, I am somewhat glad that those antennas are <10 bucks from Motorola Solutions directly, so I know my antennas are not some knock-off crap. 

And I used to use my 6550s (and other radios before that) as low power portables... but after trying a 5550e with a sweet HHCH, with 20+ miles simplex, I am never going back to these days.

Then, if you really needed longer range than that, for a SHTF situation, you should probably invest on a Yaesu Vertex FD-817 for long range comms, and not use GMRS, or VHF, including any digital modulation for that matter. A good 817 atop a high hill, or a tall mount, will probably open the entire world for comms, certainly reaching further than a 6550, 7550e, 5550e, or even the "luxury transceiver" APXs would ever dream of reaching with or without an SMA port. 

G.

I have a FT-817. One disappointment with it the upper end on VHF is 154 MHz so no weather channels. In fact many FT-817, and now FT-818, owners have the same complaint.
 

Mine also has the MARS/CAP mod. In a real SHTF situation that will be handy.

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3 hours ago, Radioguy7268 said:

And yet the same XPR7550e radio sold over in the EU as a DP4801 can be ordered up with an SMA connector (as a regular radio option, no call box option needed).

I think it's all marketing. Nothing to do with the engineers. Same reason why Motorola won't give their APX series radios DMR capability.

Interesting there is an SMA option. That suggests one could order the part(s) and retrofit the radio with the other connector type.

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1 minute ago, Lscott said:

Interesting there is an SMA option. That suggests one could order the part(s) and retrofit the radio with the other connector type.

It's a different board build. Not as simple as just ordering up the correct SMA jack & screwing it in. I'd guess that ordering in the Call Box configuration option basically gives you the same board - just flashed for North American XPR7550e firmware.

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13 minutes ago, Radioguy7268 said:

It's a different board build. Not as simple as just ordering up the correct SMA jack & screwing it in. I'd guess that ordering in the Call Box configuration option basically gives you the same board - just flashed for North American XPR7550e firmware.

Bummer.

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It is indeed a different board, Mars at Comm Support did a mod to get a female SMA on it, but is not an easy mod, certainly not for the faint of heart, involves de-soldering and resoldering SMD connectors and other small stuff. Plus there are some parts (a flange nut) that are not readily available anywhere.

As for the stud, well, I've personally had pretty good results with it. But then I also purchased the right frequency range antenna for my application, so I am pretty happy. It handily beats the SMA 6550 with any antenna I've put in there. And for when the 7550e can't reach, that is why I have the 5550e with an HHCH, 50w and a 5/8 wave flexible whip... fits on a backpack and reaches 20+ miles. Again, I use the walkie for what is good for: being carried around. Carrying around a handheld with a 5/8 whip, especially in VHF, IMO defeats the whole purpose of being hand held... but again, that is just me, and my opinion. 

G.

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Kenwood used a stud type antenna connector on their TK-270/370 HT's, not the newer TK-270G/370G models which are the typical reverse SMA type. I have an adapter for stud to mate with a BNC terminated cable. Fortunately the way the stud connector is built in to the radio the slotted nut around the stud, the stud is isolated by the way, is exposed. When the adapter is screwed in the adapter's flange part makes solid contact with the flange nut for the shield side of the coax connector.

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53 minutes ago, Lscott said:

Kenwood used a stud type antenna connector on their TK-270/370 HT's, not the newer TK-270G/370G models which are the typical reverse SMA type. I have an adapter for stud to mate with a BNC terminated cable. Fortunately the way the stud connector is built in to the radio the slotted nut around the stud, the stud is isolated by the way, is exposed. When the adapter is screwed in the adapter's flange part makes solid contact with the flange nut for the shield side of the coax connector.

Problem is that the stud in the XPR gen2.5 radios is part of the antenna itself, so it will always have leakage and the antenna you use will not perform as designed as if it were connected to a real SMA connector.

G.

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5 hours ago, gman1971 said:

Problem is that the stud in the XPR gen2.5 radios is part of the antenna itself, so it will always have leakage and the antenna you use will not perform as designed as if it were connected to a real SMA connector.

G.

I think that's because there is no "ground side" to the coax. That's always been the warning about using these antenna stud type adapters. The link below shows how that problem was sort of worked around.

https://alfonsofaustino.blog/2019/09/23/alfonso-faustino-motorola-xpr-7550e-external-antenna-adapter/

Scroll down to the photo of the top of the radio. You'll see a copper foil ground strap. When the adapter is screwed into the stud the "shell", the knurled part, make contact with that copper foil. The copper foil is run down the back side of the radio to the mounting screw for the belt clip. That screw goes into the aluminum chassis of the radio which is the ground side for RF, the "ground plane".

It's a kluge but if it works reasonably well the advantage is no modifications to the radio are required. The guy selling the adapter doesn't show what is going on with that copper foil strap, and very deliberately talks around about what it does exactly, which is his whole secret to getting it to work.

Once you figure it out you can likely buy these stud adapters for less that $7 or $8 then use some of that conductive aluminum foil tape you get at the hardware store for sealing heating ducts in place of the copper foil. Should work about as well.

The two Kenwood radios, that I have with a stud type antenna connector, has an exposed slotted ring nut around the stud, where the stud itself is isolated, sits in a Teflon bushing, and the stud is grounded to the radio's chassis. Screwing in an almost identical adapter it makes contact with the radio's ground and thus the shield side of the coax.

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2 hours ago, gman1971 said:

The stud itself is hot, the equivalent to the coax center conductor, so running that to the chassis is not a sound idea, I don't know.

G.

Yes the stud is hot, but it's not running to the chassis.

I use a very similar adapter for my two Kenwood TK-370's that use this type of antenna connector. You'll notice the stud is isolated from the connector shell in the photo. It goes through it to the center pin connection for the BNC socket on the other end.

The other photo shows the stud type antenna connector on the radio. In this case you'll notice the stud screw hole is also isolated from the slotted ring nut.

When the adapter is screwed in the shell makes contact with that slotted ring nut which happens to also be the ground side of the radio.

It looks like in the case of the 7550 that ground connection is stuck behind the plastic case so the guy had to run a copper foil strap from the back side of the radio, the mounting screw for the belt clip, up to the edge of the antenna socket well. When the adapter is screwed in the shell makes contact with that strap completing the ground connection between the coax shield and the chassis ground. The adapter he uses is likely very much like the one I use.

Stud Connector-2.jpg

Stud Socket-2.jpg

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I read the entire 'blog' and frankly, something doesn't add up. He claims that they are manufactured to his specifications, but then he has to hand assemble the parts apparently using some kind of adhesive? Then places them in a C-clamp for 24 hours to 'cure?'

Each one is carefully sanded to remove any bumps or edges. Each adapter is then tested by a Motorola service tech on his Aeroflex at a cost of $125/hr for each of three portable radios?

Then he's selling them for only $25? Something just doesn't smell right.

I did find a stud to bnc adapter several years ago, but found I'd need to use a grinder to pare down part of the shoulder collar to allow the adapter to fully screw into the radio's antenna port. I gave it up as a lost cause... 😉

Why would an actor have several EE's working for him anyway?

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2 hours ago, n4gix said:

I read the entire 'blog' and frankly, something doesn't add up. He claims that they are manufactured to his specifications, but then he has to hand assemble the parts apparently using some kind of adhesive? Then places them in a C-clamp for 24 hours to 'cure?'

Each one is carefully sanded to remove any bumps or edges. Each adapter is then tested by a Motorola service tech on his Aeroflex at a cost of $125/hr for each of three portable radios?

Then he's selling them for only $25? Something just doesn't smell right.

I did find a stud to bnc adapter several years ago, but found I'd need to use a grinder to pare down part of the shoulder collar to allow the adapter to fully screw into the radio's antenna port. I gave it up as a lost cause... 😉

Why would an actor have several EE's working for him anyway?

Oh, you’re right about the smell test. Remember he’s trying to sell these to less technically sophisticated people. All that crap about testing might be true at one point, maybe while he did the initial testing, but I’ll bet it’s just there to convince people to pay $25  for adapters he buys from a Chinese source at $3 each in bulk with a 10 cent strip of sticky sided copper foil to make the ground connection.

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