Lscott

To clarify you can't do cross band repeat on Part 95. It's done all the time on Part 97, particularly between the Ham 2M and 70cm bands. I think that's what the OP was trying to convey. It's true you can't do direct cross communications between the two licensed services. Technically there is a way to do it using the right unmodified radios. However the way it could be done would violate rules that say Hams can ONLY communicate with other stations licensed in the armature service, and except for brief one way transmissions for testing for example, one way transmissions are prohibited. I'm not advocating people do this but as a purely theatrical exercise it could be done as follows. Many Ham HT's can do split band operations, TX on one frequency while RX on another in the same band much like repeater operations. In this case the TX frequency would be one in the legal section of the Ham 70cm band while the RX is set to one of the official GMRS channel frequencies. Thus the Ham would be TX'ing on a legal Ham 70cm frequency while ONLY RX'ing on a legal GMRS channel frequency. Using the right GMRS radio that allows programming of out of band RX ONLY frequencies for monitoring and a priority RX function would be used. The GMRS radio would be programed to TX on the legal GMRS frequency the Ham HT is programed to RX on. The GMRS radio would have it's priority RX programed for the legal Ham's HT's TX frequency. The GMRS radio would then constantly monitor the priority RX frequency. Both radios are now TX'ing on their respective legal frequencies while RX'ing on the others TX frequency effecting cross service communications with unmodified radios.

I don’t know how common the practice is now but I have heard about police officers using modified Ham HT’s for communications on frequencies they are not licensed to use. Apparently it was done to hide questionable activities from being monitored or recorded by the dispatch office. Other times it was used by detectives or surveillance teams to hide communications from possible monitoring by criminals. The frequency agility didn’t restrict them to the few official frequencies programmed into their departments issued radios. Personally I did witness two uniformed police officers sitting at a table in a restaurant with an obvious Ham HT, I recognized the make and model, sitting in full view. Both officers had their official Motorola radios strapped to their belts and turned on. I’ll admit one of them might have been a Ham but it just didn’t look right.

Anyway getting back to the topic of this thread about call signs. I wish radios in general had a way to program in your call sign and have it transmitted per the FCC rules. This would be purely for convenience of the operator and a feature that could be enabled/disabled as desired. I've looked at the various builtin tone signaling options in the various commercial radios I have collected. The goal was to get a Morse Code transmission of a call sign with some "creative" setup of the signaling options. The only tone signaling options seem to be 2-tone, 5-tone and DTMF on my radios. There are also options for a PTT ID on Key-Up or Key-Off too. So far I don't see a way to do it. I think using your call sign encourages others to act responsibly on the air. If one can justify not using it then its not a stretch to justify ignoring other rules. To see where that leads a simple monitoring tour of the spectrum between 26.965 MHz to 27.405 MHz AM should prove educational.

If they have a "grandfathered" license then yes it's legal. Otherwise no. A local mall near me is using repeater channel 16, and yes they do have a repeater. The repeater is used by the mall's house keeping staff only. After some research I found they use to have a license but it's expired, has been since October of 2015! As far as I can tell it's never been renewed. I assume the FCC knows about it but just doesn't care. The only reason why I went to the trouble of finding out is the local GMRS repeater, which is only about 6 to 8 miles away, uses the same repeater channel, just a different PL tone. At times I can hear interference from the mall's repeater. I go to the mall frequently just to walk around and I have my HT with me monitoring the mall security and several of the local store's comm's. I don't use a PL tone on any of them so I can hear all the traffic. When I hear some of the GMRS uses complain about some "weird" issue with the repeater it was when the mall's house keeping keyed up their radios. Apparently they use a tone on RX and can't hear other traffic, plus they are not using the Busy Channel Lockout feature that's on just about every commercial radio out there. They have no idea there is anybody else using the frequency. Fortunately they are seldom on the radio.

I can do that, however they are not Part 95 certified. Seems like the FCC isn't too interested in busting people using good quality Part 90 equipment, but that isn't a sure thing. A lot of people are doing so without issues. Both of the radios I have are dual mode, analog and digital. Since digital is not allowed on GMRS I could use the analog half of the radios, which can do wide and narrow band FM BTW. There is only ONE repeater I've seen in the general Detroit area that's list as supporting NXDN in the RepeaterBook database last time I looked. These are the two radios I have that do NXDN. https://comms.kenwood.com/common/pdf/download/05_nx240v_340u_K_1117_typeD%20added.pdf https://comms.kenwood.com/common/pdf/download/10_NX-720HG&820HGBrochure.pdf Spending over $100 on a P25 radio is a bit outside my price range at the moment. The few P25 models I looked that seemed interesting were well north of the $100 mark. One of the other things is getting the software. All the stuff I have was freely downloaded. I think Kenwood has gotten more anal about their radio software for the newer stuff. I heard about dongles and such being necessary etc., however I haven't looked into that much. I think so far I have between 8 to 10 different packages installed to program the collection of radios I already have, and that's just for the commercial stuff.

Unless the Chinese market some really cheap P25 radios the price of the commercial ones is rather high, not something I would look at buying just for hobby use. There seems to be plenty of interest in DMR. Some decently performing Chinese DMR radios are available for a reasonable price. There is a good amount of activity on the HAM bands using DMR. I don’t expect the FCC to allow DMR on GMRS anytime soon. So far NXDN hasn’t generated much interest. I understand there is some fair level of NXDN use in Florida. My self I picked up a used Kenwood NX-340U from eBay real cheap. I was also gifted a used Kenwood mobile radio, NX-820HG. Both are the “-K2” models operating from 400 MHz to 470 MHz. So far I haven’t really did anything with them.

While that is true one thing you can do with DMR, and not with NXDN, is setup a SRF, Single Frequency Repeater, that doesn’t require an expensive set of tuned cavity filters. Several DMR radios have the functionality already builtin. This is due to DMR being TDMA verses NXDN’s FDMA mode.

Based on the good comments on the forum I ordered one myself from Bluemax49er for a Kenwood NX-820GH mobile radio I was given. I might have found one cheaper but I feel confident this will work without issues. Too many super cheap Chinese cables using the counterfeit Prolific chip that don't work out there.

If in fact the noise is coming from the car stereo it's likely radiating from the wires between the speaker output and the speakers. Many new car stereos use Class D power amplifiers. To make it simple its a switching type circuit operating at high frequency, HUGE noise generators if not filtered. If the filtering is insufficient on the amp's output you can try putting your clamp on ferrites on the speaker wires right at the point where they exit the amplifier. You might even have to shield those wires and ground the shield right at the stereo. https://www.analogictips.com/class-d-amplifiers-for-high-efficiency-switched-mode-sound/ The communications between the head unit and the main body is also likely using a fast serial communication protocol. One common protocol used extensively in automotive settings is the CAN bus. Those signals may also be a source of noise radiation and might need those clamp on ferrites too. https://en.wikipedia.org/wiki/CAN_bus

Great! Let us know how it goes when you get all the bits put together and the radio programmed. The narrow bandwidth and low power FRS channels are 8 to 14 at 0.5 watts. Channels 1 to 7 are 5 watts max and wideband, while the repeater main channels 15 to 22 are wideband and 50 watts max. I just added another Kenwood TK-3170 and my first TK-3180 to my HT “collection”. I spend to much time on eBay and can’t pass up a good deal. 8-/ The programming software for the TK-3180 complained about several features that may not work right because the firmware was too old. After contacting Kenwood support they were nice enough to supply me with the most recent version. Didn’t even fuss about it. I might have to buy yet again another different programming cable myself. I have a buddy who got his hands on a used Kenwood NX-820HG-K2 and mic from his work place they were going to dump. He has no interest in digital radios, it also does analog, so he said I could have it if I wanted. Now I need the cable. It’s not part 95 certified however. https://comms.kenwood.com/common/pdf/download/10_NX-720HG&820HGBrochure.pdf

The FCC certification grant is located here for the TK-880. https://apps.fcc.gov/oetcf/eas/reports/Eas731GrantForm.cfm?mode=COPY&RequestTimeout=500&application_id=9wLBCa2uBguLpUibGdVsCA%3D%3D&fcc_id=ALH24593210

If you're looking for the TK-880H brochure with the basic radio spec's look here. https://www.ameradio.com/doc/Kenwood_TK-780%28H%29.pdf

Many business use FRS radios that now share the same exact frequencies for simplex as GMRS. It’s legal for them to use FRS for business purposes. What you are most likely hearing are FRS radios.

Yup, the same attitude that permeated CB back in the 70's. FCC required a license but most users said screw it, or if they had one didn't ID as required. After a huge increase in the number of CB radio users the FCC gave up enforcing the license use and ID requirements, then changed the rules to make the illegal behavior legal. That way they washed their hands of having to deal with it. Hopefully GMRS doesn't follow the same path.

Some virus software will falsely flag perfectly OK files as infected. I had Norton AV years ago kept deleting the main EXE file for a $4500 microcontroller development environment I tried installing several times that I needed to use at work. I finally had to but the name of the file in an exclusion list to keep Norton from screwing with it. Very aggravating.

Looks like you need to trim your antenna. The question is it too long or too short. If the antenna provides a means to adjust the length a bit try that first. As far as the SWR going up after cutting the coax length down a bit isn't surprising. The SWR depends on how much power is output by the transmitter and what fraction of that at the end of the coax is reflected back by the antenna. A longer length of coax results in less power reaching the antenna and the reflected power, as a fixed function of the antenna match itself, is further attenuated by the extra coax length. The end result is a lower SWR as seen at the transmitter end.

All valid good points. When I was running around the country doing service for a few years I also took my FT-817 with me. Tried to get hotel rooms up on the top floor where possible. Used a small camera tripod to support some VHF and UHF antennas. Made a few surprising contacts on 2M SSB that way.

I was just thinking based on your story about getting out of the path of a hurricane and keeping track of everyone perhaps APRS would be the ticket. You can find info on it here. Basically APRS uses a GPS receiver connected to a radio which will periodically, and automatically, transmit you current GPS position to any compatible radio in the area. This data can also be displayed on a map accessible on the internet so anybody can see your location if one or more of the RX'ing radios has an internet connection. Even if there is no internet access close by APRS can use special APRS digital repeaters to propagate the APRS packets over a very large area. http://www.aprs.org/ Mapping. https://aprs.fi/#!lat=42.6206&lng=-82.9608

If the FT-818 has about the same output filter as the FT-817, I own the original version with the MARS/CAP mod, the power drops fast above the upper limit of the Ham 70cm band. Around 462 MHz it does about half power max, and at 467 MHz lucky to get 1 to 2 watts out of it at best if you are thinking about GMRS access for emergency comm's. Also the radio won't tune above 154 MHz on VHF so even on RX you can't get any of the NOAA weather stations. The later seems to be a big complaint with even the unmodified radios since the market for is is QRP operation while camping, hiking etc.

This is the mod to open up the RX and TX on the above radio. https://radioaficion.com/cms/th-d74-modification-of-the-us-version/

Try looking at the Kenwood TH-D74A if price is not a problem. I have one with the mods to open up the TX and RX ranges, https://www.kenwood.com/usa/com/support/pdf/TH-D74A.pdf I ordered mine from here and they will also do the MARS/CAP mod for you as an extra cost option. https://www.hamradio.com/detail.cfm?pid=H0-015269 You might want to look around a bit for a better price. I paid $550 with no mods when I got it a while back.

If you don't have a good ground plane for the 5/8 wave then the only alternative is using a 1/2 wave antenna, they don't require any kind of a ground plane. You need a really good ground plane for any 5/8 wave antenna to get a good match and realize the slight gain you get from using one.

Oops. The one link is for the repeater. Editing and copy paste isn’t the best on a smart phone when you’re tired. But you get the idea.

One of the first things I do when interested in a model of radio I’m not familiar with is look for any manufacturers brochures. That gives a quick run down on the features. If no luck then look for the user manual, service manuals etc. https://www.ameradio.com/doc/Kenwood_TK-7180_TK-8180.pdf http://www.repeater-builder.com/kenwood/pdfs/tkr-740-840-brochure.pdf

A bigger handheld isn’t necessarily a bad thing. If you use your handheld radio with a moderate to high duty cycle it’s going to get real hot! Some time back a Ham wrote, on another forum, he failed the output stage on his TWICE from over heating due to a high duty cycle. A larger radio has a larger metal sub-chassis, thus more thermal mass and more area to radiate heat. If you look at the typical specifications it shows 5-5-90. That’s 5 percent TX, 5 percent RX and 90 percent standby with no audio for battery life but it can also be applied roughly for thermal consideration.