axorlov

Btw, the service manual with the schematics for the V2.0 version of the radio is here: http://www.repeater-builder.com/kenwood/pdfs/tk-880h-svc-man.pdf I'd walk through it it with you, but I'm busy at my day job right now. LOL

Careful here. Pin 2 is 6V, Pin 3 is 17V. Refer to the table on Page 2 in the datasheet. Edit: these are max values, so Pin 2 should be around 5V, and Pin 3 is around 12V.

Yes, this is the part. I agree with Sshannon, oscilloscope would be needed. But here is the datasheet for the PA, just in case: https://www.mitsubishielectric-mesh.com/products/pdf/ra45h4452m.pdf You can quickly check the voltages on pins 2 and 3 (refer to Page 2 in datasheet). Maybe the PA is fine, but there is no driving voltage. It also may have an effect on the audio amplifier.

I have both TV and GMRS antenna on the same mast. TV antenna is UHF yagi and VHF log periodic combination, I do not remember the model. TV antenna at 10', and Diamond X50NA is 8' above the TV antenna. I was a bit worried that I will fry the TV tuner frontend, but so far it did not happen in roughly 5 years. TV tuner is Hauppauge WinTV-HVR-1250.

You have dummy load or proper antenna on the other side of your power meter, right? Right?? If yes, that is a very strong hint that power amplifier is a toast. I'd say 99% probability. The HT nearby receives the very low radiation from the internal low-power traces and wires.

I usually don't! But you keep up a good job, the fixation is telling! Signed: some people

Both of these questions pop up regularly, on a bi-weekly schedule. The forum has plenty of info on both Ed Fong antenna and grounding. Use search button.

He can't shut up. His girlfriend cheated on him with some people, he can't get over it and now has a whole youtube channel dedicated to his misery.

Database from radioreference.com is a good tool for programming scanner. https://www.radioreference.com/db/browse/ctid/2275 Looks like Lackawanna county is all analog FM and Narrow FM. No P25, no trunking. Just couple of DMR licenses here. Correction: PA-STARNET is P25, but this is it.

Nagoya NMO-200C on GMRS frequency is a colinear array of two 5/8-wave elements (according to what I see on baofengtech and amazon). I hazard to guess it will work acceptable without ground plane. There are plenty of examples on this forum of 5/8 antennas on all kind of Jeeps installed without ground plane on lip mounts, tailgates, spare carrier, etc. Ground plane will help, but not required, imo.

Was used as behind-the-horizon and broadcast all the time back then, by lighting up the clouds above.

I actually understand what Prof. David P. Reed says. But David Weinberger, the journalist, does not. And people (simpletons on slashdot) who are retelling the story, attempting to simplify it even more, do not understand even David Weinberger. Poor souls, when they grow up and get out of their mother's basement, life is going to be tough for them. And the second link can be summarized by: design the road in the way to eliminate signs. Doh! His first husband must've been Captain Obvious.

I would keep 5/8 whip, if I was you. Before getting other antenna, I would sort out measuring equipment.

Ah, the famous SW-33. I have one and it is garbage. I also have Diamond SX600. The SW-33 and SX600 mostly agree with each other when measuring on 2m, but SW-33 is way off with power and SWR measurements on 70cm and GMRS.

Marketers, who create such work for printed materials and web, often have no clue. It maybe a helical antenna (very like it is), it may have total length of the wire at around 5/8, but it is not 5/8 antenna.

3.5" antenna can't be 5/8. 5/8 wavelength on GMRS frequency is around 16". When you are saying you've got better test results, you mean better measured SWR? If yes, it just demonstrates that more power is absorbed by an inefficient antenna and not being radiated. Converted to heat. There is a device, called Dummy Load to test transmitters. It usually has perfect SWR 1:1 and designed to not radiate at all. 1/2 wavelength antenna does not need ground plane. 5/8 antenna needs ground plane to provide 3 dBd gain and correct flattened pattern, however, it will work without ground plane with reduced radiating efficiency, distorted pattern and higher SWR. You will have higher common mode current on your coax, but that might still be ok. Without ground plane it likely will be about equivalent to the 1/2 antenna with higher SWR. P.S. I just re-read the thread, it seems that your problem is low measured power. It could be that your power/SWR meter is to blame, or your antenna, or your cable. If you buy aforementioned dummy load rated for 100W and 500MHz, you can test your output power safely at two places: at the radio and at the antenna. Difference will show how much power is absorbed by the coax. Also, your SWR meter should be rated for at least 500MHz, CB meters do not work at these frequencies.

The usual NMO-mounted antenna is only a half of the antenna, the other half is a ground plane created by a conductive flat roof of the vehicle. The threads that are holding NMO antenna in place are connected to this ground plane, while the center pin in the NMO mount is connected to the whip of the NMO antenna (as was pointed out above). The O-ring is simply to keep water out of the connector (as was described above).

If the fuse and it's holder is on the wire, your best bet would be amazon, local car parts store and ebay, in that order. Nothing special about #12 stranded wire with a fuse, it does not have to be specially designed for GMRS. T-connector, also known as Kenwood/Yaesu/Icom power connector can be found on amazon or ebay.

In this case you should at least ground the shield of the coax before it enters the house. This would be a minimum requirement, because your antenna will accumulate static charge just from the wind, no lightning necessary. Give static a path to the ground other than through your radio. Bulkhead N or PL-type connectors can be used at the bottom of your mast or at the entry point into the house. Better solution is to use lightning arrester certified for 500MHz, as mentioned above, and a proper grounding wire and a dedicated grounding rod near the mast, bonded with the house grounding rod by #6 or bigger wire. This method is according to the code. I myself do have rod for the mast, bonded with the house ground by #4 wire, but I only ground the shield of the coax. Where I live, lightnings happen once in 10 years.

Quick and dirty test for common mode is to measure SWR when not touching the outside of connector with your finger, and then measure SWR again when touching connector with your finger. No change in SWR indicates that there is no or negligible common mode current, while huge swings (4:1 or so) indicate there is a very considerate common mode current.

Don't have pictures, sorry. My portable setup is FT-817ND + Emtech ZM-2 manual tuner + 20ft telescoping fishing pole + about 60ft of wire. It is more a hiking setup, than a car setup. I'm currently building 3500mAh batteries from cheap LiPO chinese cells that will fit into the FT817 battery compartment. Three of these batteries will serve me for a week, easily, without needing for recharge. I'm not really interested in contests, SOTA and such, the setup is mostly to have a reliable comms to base camp, and sooth my thirst for an engineering challenge of having a reliable comms when resources are limited.

Looks good! You will likely need a common mode choke on your coax, but maybe you could get away without it. And clean the mess on your workbench! It affects the SWR. And the special praise for this tool (I do not know the english word for it, the push driver maybe?) with the purple handle, in the middle of the picture, that looks like a long screwdriver. I haven't used it myself in 30 or so years, and this is the first time I see it in the last 20 years in the the time-relevant picture. What other ancient wood working tools do you have? Judging by the looks of your workbench you may have some!

Hell yeah!!! It has INCREASE knob! But wait a sec. 10A Max for 12V continuous and 20 A for intermittent. It will work for a certain radios that do not pull more than 10A for continuous and 20A for intermediate duty cycle. If it is truly 12V and not the 13.8V, you will see max radiated power reduction of around 10% with modern radios. But maybe using INCREASE knob would allow to pull the 13.8V with 10A?

Well, yes. This is why I said at 450MHz. The 0.6dB at 100ft is nothing in my book, and in my playbook only. Your playbook may be different. All depends on use case.

400MAX has stranded copper central conductor like LMR-400-UF and is a direct burial like LMR-400-DB (which has a solid aluminum copper-clad center conductor). The difference in loss at 450MHz is negligible between the two. There is must be a catch somewhere, but I haven't found it so far. I use 400MAX for the last 10 years buried and on the very hot roof in sunny CA.