Lscott

Just when you thought this would end. We need a wooden stake. This vampire just won't stay down.

At least you get paid for the trouble I assume. Me, it's all on my time.

This is an export for an experimental code plug from KPG-166D for my TK-D300 radio. KPG166D_TK-D300 Export.itm.csv You'll notice none of the zone names are in the file, only identified by the zone number, so importing this data will wipe out my zone names at a minimum. Also other crap gets changed, I think the memories all get set as added to the scan list for example, then I have to go through each one to uncheck the scan add box. PIA. The only thing I found useful about the import function is it saves me the trouble of reentering a bunch of frequencies when building a new code plug from scratch for a new radio model I got. The radio used is in the link here. https://forums.mygmrs.com/gallery/image/255-tk-d300e-fmdmr/

Your idea might have some merit. Doing the manual editing in Excel might be easier than flipping through various windows in the programming software. Reimporting the data also has a nasty habit of wiping out the zone names I’ve assigned and resetting some options back to their defaults. I have to renter all that again by hand.

Not all of Kenwood’s software has an export function, which seems it just a CVS file. I can change the file extension to CVS and Excel reads it just fine. Sorting in Excel won’t help. I’ve already tried this. The exported data had the list entry number on the same line as the user ID’s and talk group numbers. Yes there are two lists. The big one is the talk group one. If you do a sort it looks petty in Excel. When you reimport the data the talk groups get stuck back in the list corresponding to the list number you see in Excel. You end up with exactly what you started with, a mess.

I don’t program up any of my digital radio unless I need to make a change, or making a code plug from scratch, which lately in about never. That can be a PIA when the repeater owner(s) change talk groups and or networks. You discover that when previously working stuff quits working. Then trying to find the info on what is currently supported is a crap shoot. Sometimes Repeaterbook.com helps, if not then you’re off looking for the repeater’s website, if there is one. Sometimes I think the repeater owners change stuff around just to torment people. The way I currently try to keep the mess organized is using one “zone” per repeater. In each zone I use one memory entry per talk group and slot number. The commercial radios I use don’t support front panel programming, like you get with Ham gear, so this all has to be done ahead of time. Some of the radios have the ability to select user ID’s and talk groups from the internal lists stored with the code plug through a menu function you assign to a PF key. The fun starts when adding in more talk group numbers. Those go into a list. The list is numbered from 1 to whatever size the radio software/hardware limits are. When a memory is programmed you use the list entry number corresponding to the entry for the talk group you want. Having a lot of talk groups in the list means constantly scrolling through the list looking to see where it’s at to get the list entry number. Sooner or later the list is a mess of out of order talk groups. Moving the talk group numbers now means your memory setting for the talk group list entry now refers to the wrong talk group. Now you have to manually go through every programed memory and update the talk group entry list number. I’ve done that more that once. There doesn’t seem to be a way to let the software sort the list and update the memory programming.

You might be right on this one.

I feel sorry for them if they are reduced to using cheap Chinese radios in war time. You are literally betting your life on a $25 radio that will likely fail the first time you drop it on a hard surface. It's as sad as these guys at the following link too. https://radiofreeq.wordpress.com/2016/01/19/militia-radio-frequencies/

You may need to do a model if the metal structures are a 1/4 wavelength or larger in size in the immediate area of the antenna. Things like roofs, hoods and so on can affect the radiation pattern. Those structures are approximated using a grid of wires in the model. This is an old model I did looking at the radiation pattern for a 2 meter horizontal loop antenna using a magnet mount on the roof of my old Jeep. I wanted to see if the 18 inch mast they sell with the magnet mount was sufficiently high for good performance. Doesn't look very good. Both photos have the same exact 3D orientation. As you can see there are two main areas of high signal radiation. One is mostly directed skywards, useless. The second in in a horizontal plane, which is where you want it. Because the roof is a rectangle the horizontal part is not symmetrical, more signal in the direction of more metal in the roof.

That might not be as funny as it sounds. I did read months back that people were buying up cheap radios to send to the Ukrainians. Whose to say the Russians aren't using CCR's. Since they seem to be getting more and more warm and fuzzy with the Chinese you might be right.?

If it is then this is the brochure for it. https://www.motorolasolutions.com/content/dam/msi/docs/EA_Collaterals/ENGLISH/MOTOTRBO/Portables/DP4000_DataSheet_ENG_lor.pdf

Given how Motorola has entitlement keys you write to a radio to enable various features I just can't see how anyone could make a definitive claim. I have a bunch of Kenwood radios, and a few Motorola's, myself and some look identical. Can't tell them apart without looking at the tags on the back side under the battery pack.

OK. My guess is it was the power transistor that failed. That can happen for several reasons. I listed a few below but it's not all inclusive. 1. It was improperly installed. The screws were not torqued down correctly. Too much, too little or no thermal compound used between the transistor's mounting flange and the heat sink. 2. High SWR on the amplifier output. May not have to exist for very long, monetary, to blow the transistor. 3. High voltage transients on the DC supply. 4. If any kind of "bias" is applied to the transistor it wasn't designed right, or the temperature sensor is not installed VERY close to the transistor. That can cause the transistor to go into thermal runaway which will destroy it in seconds. This applies to bipolar types. FET's are different. 5. The transistor is being used beyond it's published power ratings. One might get away with this so long as the duty cycle is kept low.

What do you mean by "the RF chip"? I only see one small black IC chip on the board. You're not mistaking the large power transistor that's screwed to the heat sink are you?

Any clue as to exactly what failed in the 3 amps you had? If it's the same failure and knowing what it was there might be a fix for it, or avoiding whatever it was that precipitated the failure.

I've attached a section out of the function reference guide for the NX-200/300 series radios for the transparent data mode. You have the NX-5000 series which I assume the functions will be similar. The HT's don't have any hardware flow control so the TNC emulator has to implement some form of software flow control. The mobile radios might have the hardware flow control on the interface port. Transparent Data Mode.pdf

Have you tried doing any data exchange using DMR or one of the other modes? From what I've read using the "narrow", not the "very narrow" mode on NXDN you can get a faster data rate than with DMR, which is limited by the TDMA method used. The Kenwood radios I have include a TTL level serial port that can be configured for data transmission. The radio is used as a modem with the native digital voice mode doing the communication protocol to facilitate the exchange. In the programming software it's configured as either "Transparent" or "Transparent 2" for the protocol. Using the builtin serial port one no longer need a "packet" interface, which is basically a direct connection to the modulator input and discriminator output. Then you had to screw around to get the right signal levels for the frequency shift required. The serial port, and the radio's native digital mode, takes care of all that for you. What I'm looking for is software to emulate a hardware TNC. Just about everything I've found either won't work on the newer version of Windows, or requires DOS and wants to interface to a sound card, which isn't needed using the digital radio. I've been told some had success using D-Rats, but thats aimed more towards D-Star specifically.

Can't see what kind of radio it is, just saw it from the backside. They likely would try to recover any radio they spot. If it's a military grade or commercial it could be a digital type and mostly likely using encryption. They would be interested if the later was the case due to any encryption keys. The radio might have been lost before it could be killed and the keys wiped. Of course the last possibility is it's a "plant" left there hoping it would be recovered. Then it could be traced or used to supply false information to the Ukrainians.

I think I just go back to playing with my D-Star, NXDN and P25 radios.

There are two models of this amp. One is usable for TDMA type radios, DMR mode, whereas the other one isn't. Are people sure it's the AMP-U25 and not the AMP-U25D? Could the amp have been misused by any chance? A high SWR between the amp output and the antenna is likely a good indication the amplifier is generating a high level of harmonics, and other garbage, that's being reflected back to the amplifier. The amp may have been over driven too. Some radios are not well behaved when the power is turned down. I know the old Icom IC-706MKIIG had a nasty habit of spiking up to full power very briefly before dropping down to a lower set power. I have a new AMP-U25D version, haven't used it yet, that is rated for ALL the common digital modes. A comment was made by a poster that a "chip" failed in their amp. I've attached a PDF file, from the FCC, showing the internals of the -U25D version. I'm going to guess it's similar to the -U25. Does anything in the photos look like the part that failed? Internal-Photos AMP-U25D.pdf

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This is the one thing that bugs me, mostly with DMR. That's the multiplicity of networks. I try to program up my radios and every repeater seems like they have to use a different network for linking. If you're lucky the talk group numbers are the same, but not always. Then you have to jump through hoops to link from one network to another if the one you want is on the "other" network. DMR is enough of a pain as it is to program up a radio without the above BS on top of things. Here in Michigan for example a number of local repeaters use the Mi5 network. Dah! https://w8cmn.net/mi5-sites-talkgroups/ And a de-funked network. https://dmrx.net/dmrx-core.html And this is an example of a repeater that's a bit more changeling to program. It uses several different networks and talk groups. http://n8noe.us/DMR/dmr.html

If Kenwood ever started to produce the TH-D74A again in a DMR format they likely couldn't keep them in stock on the shelf. I would be interested in buying one just to get away from the Chinese stuff.

Thanks for the comments. This was something I was curious about.