XPR 7550e ... just wow...

[gman1971]

Speaking of the R7, here is an unboxing video

 

[gman1971]

Side by side of the two radios. XPR7550e and R7. In this pic its noticeable bigger too... yet another Con in my book...

 

G.

[PACNWComms]

Was waiting to see this comparison at some point. Thank you for posting. That bigger display also means less likely for my employer to purchase these for "fire" personnel. The biggest deal breaker though is the Motorola Trbo Ion series accessories that the R7 uses. 

[gman1971]

1 hour ago, PACNWComms said:

Was waiting to see this comparison at some point. Thank you for posting. That bigger display also means less likely for my employer to purchase these for "fire" personnel. The biggest deal breaker though is the Motorola Trbo Ion series accessories that the R7 uses. 

I think at this point the APX900 is a better deal than the R7. IMO. With the APX900 you get an XPR7550e with SMA, full FPP, and all the accessories/batteries of the APX4000.

G.

[Lscott]

51 minutes ago, gman1971 said:

I think at this point the APX900 is a better deal than the R7. IMO. With the APX900 you get an XPR7550e with SMA, full FPP, and all the accessories/batteries of the APX4000.

G.

It does look like the XPR7550 but it's a P25 digital mode, not the DMR digital mode. What they mean by "affordable" for a P25 radio I don't even want to look. P25 radios are priced stupidly high in general.

https://www.motorolasolutions.com/en_us/products/two-way-radios/project-25-radios/portable-radios/apx900.html#tabproductinfo

I've purchased a number of my Kenwood NXDN radios with almost the same spec's as the P25 models for a whole lot less money. That's comparing the NX-200/300 to the TK-5220/5320 models. I do have some P25 radios, when I can find one I won't get raped over on price.

https://pdfs.kenwoodproducts.com/2/NX-200&300Brochure.pdf

https://comms.kenwood.com/common/pdf/download/TK-5220_5320_Specsheet.pdf

[gman1971]

@Lscott

They might be cheaper, but cheaper is always relative, right?, as they are not comparable in terms of performance, so yeah, you pay less, but you also get a lot less performance too.

Also, the statement "Almost the same specs" is rather misleading, and it sounds just like a used car salesman trying to sell you a clunker, as Kenwood radios have measurably inferior receivers compared to the Motorola XPR/R7 radios, and the APX radios are one level above the XPR/R7 radios.

I was referring to a company upgrading radio equipment from the Motorola XPR series, then I'd go with APX900/APX4000 over the R7 route, you get to keep all your accessories and batteries.

The only other radio manufacturer I'd consider trying at this point (and that is b/c I don't have any ISOtee data on them) is ICOM... 

G.

[Lscott]

37 minutes ago, gman1971 said:

@Lscott

They might be cheaper, but cheaper is always relative, right?, as they are not comparable in terms of performance, so yeah, you pay less, but you also get a lot less performance too.

They are basically the same radio. One of the interesting thing is while using the engineer/lab version of the software and looking at the radio's info read output I saw it also had two serial numbers. One for NXDN and the other was for P25. Go figure that one out.

That sort of goes along with a post, which I can't go back and find, where the claim was made that the radio could be switched between the two modes with a firmware change. It sort of makes sense since the vocoder is done in software running on a separate DSP chip in the radios. The DSP chip does the encoding/decoding and protocol work. Changing the DSP code would be the only thing required so long as the modulator could generate the right RF signal.

Bench marking a digital radio is not like doing an analog one. For example with DMR the bandwidth is 12.5KHz. With NXDN the much more narrow bandwidth is 6.25KHz. The narrower bandwidth also rejects more noise compared to the main signal. That can have the effect of improving the signal to noise ratio over lets say DMR. I don't have any proof, since one can't see the source code for the DSP, but some of the filtering is likely done there since it's possible to implement far narrower filters, than what is possible in analog hardware, WITH repeatable characteristics.

You can't ISOtee test something like this since you don't have access to the data stream coming out of the digital filter to gauge it's effectiveness. It's all internal to the DSP. I wouldn't be surprised if Motorola wasn't doing something similar too. You can implement DSP algorithms in FPGA hardware instead of a DSP chip. I believe Motorola does use an FPGA in their radios. 

The manufacture may have skimped a bit on the analog half since the real market for the radio is for digital use. The reason why the analog section is there is an upgrade/migration path for the end user. They don't expect, or hope, the user will use the radio for analog long term. Otherwise why buy one? They have cheaper analog radios.

I have some idea what DSP filters can do. I had a project where I downloaded some waveform data from a digital scope into a package called MathCAD. It has some DSP and FFT/IFFT functions in it. I used those to make a filter to get out the high frequency noise due to the switching transients and ringing in the scope data. It was amazing to see just how well that works.

[gman1971]

@Lscott

Respectfully, no, they are not. If you believe that they are, then that is where the problem lies.

Again, respectfully, chip encoding/mode is irrelevant to the conversation, AMBE, IMBE, EMBE... we are talking receiver performance here. Vocoder is the same on all those radios, AFAIK. Maybe Kenwood used the "economy vocoder model..." but we'll probably never know.... 

Generating RF signals is not relevant to this conversation either, again, we are talking receiver performance.

If the DSP can't get the signals in, then there is nothing a DSP can do. Simple as that. I am also well aware what DSP can and cannot do, and magic is not on the list. A system is measured by its weakest link, and in Kenwood's case, its the receiver, which happens to be the first link in the chain, which is utterly inferior. If you don't believe this, then again, that is another thing you need to come to grips with.

The receiver of a radio is exactly the same for digital and analog, or do you believe digital signals are different than analog signals? Or is it a lens HD or SD? or does the muffler need new bearings? or maybe need to add some blinker fluid? Sorry to break this to you, but Kenwood didn't skimp on stuff on purpose, otherwise if they could've one-up Motorola in receiver performance, they would've done it... but they lack the technology and the know-how that Motorola has at this particular moment in time. In 10 years, who knows, right?, but now, here and then, they just don't.

Remember that Quantar thread smashing the teeth of a Kenwood repeater?, yep, well, that is not just a one-off lone instance in this forum, that is everwhere, everyone, every person I've talked to who've made the move from other brands to Motorola... they all report increased performance in coverage and audio quality... and this is my experience as well. Again, why do you think professionals use Motorola equipment everywhere? If they could save a buck, or two (or a thousand), they would've used 50 dollar Kenwood NX-200 b/c they are the same as APX900 (XPR7550e) performance... right.

An ISOtee of -120 dBm vs an ISOtee of -112 dBm, you have a 8dBm dynamic sensitivity difference that no amount of DSPing in this Universe will make up for it... and that is the kind of dismal performance between the two brands. This is an XPR7550e, not an APX4000, which probably has even better dynamic sensitivity over an XPR7550e... but hey, they are "about the same" as the NX-200 right?

Benchmarking any receiver can be done with an ISOtee test, if you don't believe that then that is another thing you need to work on.

'll repeat what I said on the Quantar thread here again: I sold ALL my inferior radios and went Motorola all the way. Never looked back.

Now, if you so strongly believe Kenwood is "just as good", then by all means, believe whatever you want to believe, but believing in something when there is ample data and usage statistics from professionals from all over the world that disprove your belief, along with my own measured data, seems kinda weird to me... but again, its not my money.

G.

[PACNWComms]

5 hours ago, Lscott said:

using the engineer/lab version of the software and looking at the radio's info read output I saw it also had two serial numbers. One for NXDN and the other was for P25.

From my time as an engineer with in the then JVC/Kenwood Group, the idea was that Kenwood radios could be software/firmware upgraded at a later date to P25 specification if needed, as the hardware already met spec in order to get grant money for public safety entities. 

Kenwood could beat the competition on price, and smaller municipalities had a radio that could in theory be upgraded to P25 capability for actual use, but still had enough hardware compatibility for those grants.

You could save thousands per unit, and still con the government into receiving grants. The problem with this, is too many Microsoft software engineers that lacked radio knowledge and experience. It was common for a radio that later needed to actually work in P25 spec, to need to be sent to Kenwood for hardware/firmware/software upgrade to actually work in P25 mode. Also why there are so many 5000 series radio models as they broke model out by what was actually shipped. Sort of like having another car model for each option package you bought. Kenwood lost a lot of "street cred" with these situations. Including me, seeing it within the Group. Some situations also involved running out the warranty clock on fixing those problems. This happened with: Viking, EFJohnson, Kenwood, Zetron, and JVC video divisions.

[PACNWComms]

To add in for the dual serial numbers you noted, those are for different boards inside the radio for NXDN and P25. Different manufacturers made each board, then they get placed Lego style inside the chassis as ordered.

You wait too many software revisions later to upgrade licensing to actually use that P25 board, and the radio needs to be sent to Kenwood for a new P25 board with newer firmware that will actually take the Kenwood generated license to activate that function at that time, then find out you are out that money if the radio does not work in P25 as needed, when needed.  

The idea was to be eligible for federal grant money for P25 capable radios for public safety, with the intent to be like Motorola and their Entitlement ID's for CPS, or unlocking features within the individual radio.

[Lscott]

4 hours ago, gman1971 said:

 

Now, if you so strongly believe Kenwood is "just as good", then by all means, believe whatever you want to believe, but believing in something when there is ample data and usage statistics from professionals from all over the world that disprove your belief, along with my own measured data, seems kinda weird to me... but again, its not my money.

G.

I was commenting about similar Kenwood radios for performance.

The contrast between how DSP is implemented, DSP chip verses doing it in an FPGA, is a choice between performance verses cost. Designers have used FPGA when the required performance can’t be met with a DSP type processor. With an FPGA the “processing” can be done in parallel. 
 

With digital radios the important metric is BER, bit error rate, or how well the radio can recover the digital data. While the analog section might be superior if the DSP algorithms suck then that advantage disappears. Without access to the code there is no real way to know. 
 

https://www.electronics-notes.com/articles/radio/bit-error-rate-ber/testing-bert.php

https://www.researchgate.net/profile/Steve-Russell-5/publication/265842942_DSP_Demodulation/links/541c7d540cf2218008c9d275/DSP-Demodulation.pdf?origin=publication_detail

To clarify things a bit when you mention your ISOtee tests it would be beneficial to mention which models you tested. Simply claiming one manufacturers equipment is superior likely isn’t true for their complete range of products nor newer or older versions of the same model, or even between older verses newer models. Designers very often change designs and or critical parts that affect performance even if the model name is not changed. Given the crazy parts shortages a lot of that is going on right now. I’ve been in the middle of this mess with multiple circuit designs for the equipment the company I work for produces, and no we haven’t changed part numbers etc. as far as the customer knows they are getting the exact same thing.

[Lscott]

2 hours ago, PACNWComms said:

To add in for the dual serial numbers you noted, those are for different boards inside the radio for NXDN and P25. Different manufacturers made each board, then they get placed Lego style inside the chassis as ordered.

You wait too many software revisions later to upgrade licensing to actually use that P25 board, and the radio needs to be sent to Kenwood for a new P25 board with newer firmware that will actually take the Kenwood generated license to activate that function at that time, then find out you are out that money if the radio does not work in P25 as needed, when needed.  

The idea was to be eligible for federal grant money for P25 capable radios for public safety, with the intent to be like Motorola and their Entitlement ID's for CPS, or unlocking features within the individual radio.

Well that helps clear up the mystery a bit.

I’m mainly interested in the older Kenwood radios. I’m going to guess that the problems are more with the newer NX-5300 series radios that claim they can do two out of three digital modes, P25 - NXDN - DMR, switchable by the user. I’m not interested in getting any of those simply due to the license key crap they implemented like Motorola has done with feature upgrades on their radios.

I see more of these showing up on the used market, I assume for a reason. Some of the older Kenwood radios are damn hard to find, at least for a price that won’t bust a bank. The older NXDN radios aren’t too hard to find and for a reasonable price. I’ve picked up some of the NX-200’s and NX-300’s on eBay.

https://comms.kenwood.com/common/pdf/download/301_NX200-300.pdf

 Now the P25 stuff is a different story. The few TK-5320’s and the TK-5220’s in particular are hard to find and expensive used. I’m still looking to bag a second TK-5220 if I can find one that the seller isn’t asking a stupid high price for it. I have a couple of the TK-5320’s now.

https://comms.kenwood.com/common/pdf/download/TK-5220_5320_Specsheet.pdf

I just picked up a NX-320K radio. I’m toying with the idea of trying to change the market code to make it a NX-320E. Those apparently can get a different firmware loaded to run dPMR digital voice mode. It’s almost unknown here in the US, this is far more common in Europe. I already have the specific radio programming package for that, KPG-161D. There is mention of the modification in the brochure.

https://kenwoodme.com/wp-content/uploads/2018/03/03-NX-220_320-1.pdf

This is a hobby for me, I’m not running a business so trying to squeeze every last db of performance out of a radio is not my top priority.

[gman1971]

@Lscott

You know this isn't a hobby for me, it never was. Even when I was very active in GMRS, my ultimate goal was always to build a bulletproof family intercom system; not a tinker toy, not hacking radios just to see what happens.

Now, when anyone is trying to convince me (and what appears to me as misleading others) with hypotheticals, diagrams, or whatever other gimmicky buzzwords, claiming that certain radio brand, radio model or a radio equivalent to what I've tested (and deemed inferior) are "just as good" to any other brand, be it Motorola, Wertex, Kenwood, for example if someone tells me a BF-1801 is "just as good" as a Vertex EVX-539, then I call it out, and the thread turns into this. Motorola happens to be ATM at the top of the food chain, regardless of your opinion, agreement or lack thereof.

Having range, reliability, battery endurance, and radios that mesh and work seamlessly together as a system, with ZERO tinkering are paramount qualities I seek in a radio system, so I buy accordingly. Keyword: Radio System, as in: a bunch of radios that seamlessly work together under my own infrastructure; and it so happens that Motorola, for all their faults, they've spent a great deal of effort in trying to make just that, even though sometimes they screw up.

Now, what makes you think that I just simply "claim Motorola is better" without any proof? Let's see.... when these qualities I've listed above are required in a radio system, Motorola is almost always the radio system of choice, and not Kenwood. Now, I do see brands like Kenwood, and other lower tier brands used in budget conscious applications, when not all the above qualities are required.

In fact, it would've been great (to me, and my wallet) finding another less expensive brand than Moto$$$ that provided what I needed. Unfortunately, tho, after giving it a good try (and rather expensive in the long run), it became rather clear that budgety stuff, tinkering and being cheap wasn't going to cut it for my application, so I had to go all the way, and as it turns out, I've never looked back since then. Just like the guy with the Quantar, or a few other people who I've talked to over the years in different forums. There is a reason why everyone is competing with Motorola. Heck, even a former engineer from Kenwood states that their radios are not that great.

And to reiterate, cheaper radios and CCRs DO they do have their place and purpose, as they can get people interested in radios, but not necessarily keep them interested for long once the shortcomings start to pop. Nowadays, given the sole fact that cellphones exist, and that people don't want to tinker with stuff anymore, and that they just want reliable comms, which is what a cellphone offers, when they get sucked into the cheap radio utopia that they'll have great everything for pennies on the dollar, etc, so they march on based on this premise, tinkering with their new toys at first, until realization that its harder than they thought sets in, then no more. Personally, I hated every minute of tinkering with substandard equipment just to barely get the dang thing to work, (and the next day it wouldn't work anymore), nor it should be for anyone aspiring to have a viable alternative to a cellphone system using GMRS or LMR.

Oh, and IIRC, GMRS was never meant to be a hobby, right? ham radio IS a hobby, GMRS is a family communication service.  Using GMRS radio as a hobby is just missing out, if you really like tinkering with radios, then get the technician ticket. Now, while both "licenses" use radios, each serves a completely different purpose: Ham is meant to tinker with radios, for the sake of radios, to talk about radios, dream about radios and ego-stroking each other over 2m until the TOT timer in the repeater runs out..., whereas GMRS is meant for me using a radio so I can ask my wife if she wanted carrots or broccoli b/c I don't see neither of those two listed in the shopping list... and preferably with a range exceeding the corner down at the end of your street.

G.

[Lscott]

I would still like to see which specific models were tested and the data you collected. That’s the relevant point. Is it just one particular model or the manufacturers whole product line that’s better or inferior to another’s. I suspect it’s just one standout model. 

[gman1971]

We can take this offline.

[Lscott]

The radios I do own I would be interested in any test results would be the following:

HT and QRP radio Collection:

Tri Band:
TH-D74A VHF/UHF tri-band analog/D-Star Digital (MARS/CAP mod)
UV-5X3 VHF/UHF tri-band
TH-350 VHF/UHF tri-band 128 channel

Dual Band:
TH-G71A VHF/UHF 200 channel (MARS/CAP mod)
TH-G71A VHF/UHF 200 channel (No mod's)
TH-79A VHF/UHF 80 channels xband repeat built in
UV-5R VHF/UHF 128 channel
D878UV VHF/UHF 4000 channel analog/DMR Digital
KG-UVD1P VHF/UHF 128 channel

Multi Band:
FT817 HF/VHF/UHF (MARS/CAP mod)

VHF:
TK-270G-1 VHF 128 channel
TK-2000 VHF 16 channel (International Version)
TK-2170-K VHF 128 channel
TK-2140-1 250 channel (European Version)
TK-2140 US version 250 channel
TK-2160 VHF 16 channel
TK-2360 VHF 16 channel
TK-2180 VHF 512 channel
NX-200 VHF 512 channel analog/NXDN Digital
XPR6550 VHF 1000 Channel analog/DMR Digital
TK-5220-K VHF 512 channel analog/P25 Digital

UHF:
TK-370-1 UHF 32 channel
TK-370G-1 UHF 128 channel
BF-888S UHF 16 channel
TK-3170-E UHF 128 channel (European Version)
TK-3170-K UHF 128 channel
TK-3212L UHF 128 channel
TK-3212 UHF 128 channel
TK-3173-K UHF 128 channel
TK-3160-1 UHF 16 channel
TK-3360-1 UHF 16 channel
TK-3140 UHF 250 channel
TK-3180-1 UHF 512 channel
TK-3180-2 UHF 512 channel
NX-340U-K2 UHF 32 Channel analog/NXDN Digital
NX-300-K2 UHF 512 channel analog/NXDN Digital
NX-300G-K UHF 512 channel analog/NXDN Digital
NX-320-K2 UHF 260 channel analog/NXDN Digital
TK-D340U-K UHF 32 Channel analog/DMR Digital
TK-D340U-K2 UHF 32 Channel analog/DMR Digital
TK-5320-K2 UHF 512 channel analog/P25 Digital
XPR6550 UHF1 1000 channel analog/DMR Digital
XPR6580 UHF 1000 channel analog/DMR Digital
T5720 (Motorola FRS Radio)