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This question has been coming up a lot lately... "My 50w Radio Doesn't Make 50w. Why?" I figured I would post quick highlights of the more common items that lead to low power. This is just a list of a few items. If anyone would like a bit more detail, just ask and myself or one of our seasoned operators will be happy to help with further explanation. One of the most common issues that will prevent you from reaching a full 50 watts is the manufacturer. They have to have their device certified by the FCC in order to be sold in the US. The radio needs to be sold in the configuration as tested and certified. If the radio or any subsequent builds tested exceed 50w, even if it's not intentional due to something like component tolerances, the manufacturer will either not get or lose their certification. To avoid risk of losing certification, when the radios are designed, they are designed to operate at much less power. I know for a fact that many popular brands target 46w, so they can round-up to 50w for advertising. However, manufacturing tolerances allow for +/- 4w. So, a properly running new radio under the absolute best conditions could make as much as 50w or as little as 42w. Again, only under perfect conditions. Those perfect conditions are typically 13.8vdc "at the radio" (not at the power source), almost unmeasurable losses due to test gear insertion, a proper dummy load, and being on the channel/frequency that the manufacturer centered up the transmit power to. The following issues are just a few that will lead to less than ideal conditions. - Not testing on the channel/frequency that the manufacturer tuned for max performance. - The power source is too low. - Power cables are too long, lending to too much voltage loss at the radio. - The power cables are too thin for the current draw and length of the power cables, lending to too much voltage loss at the radio. - Power cables have connections that are crimped instead of soldered. - Corrosion at the battery connectors or other connectors in the power lines. - Improper grounding of the radio. - Improper grounding of the antenna. - A bad or poor performing antenna. - Bad or poor performing antenna cables. - RF interference from something in the vehicle that is close to the radio, causing improper performance. There can be more than this, but in my decades of experience, these are the top problems I have seen. Below is a video showing the difference between my amateur radio on my bench vs installed in my Jeep. Even mine isn't perfect because I wanted to use the factory auxiliary switches, as well as Power Pole connectors for easy removal, and I don't mind losing a few watts compared to the convenience.

Duplexer needs tuned. No way around it. Its not on the frequency you are trying to use.

I've spent too much the last few weeks. I located a vendor in the Netherlands that still had, or access to, the discontinued Kenwood TK-D300E radio. Just got an email from them with tracking number so it should ship today or tomorrow. With just the belt clip and radio core, both new, cost me 271 Euro's with tax and shipping. That now gives me two, one used and a new radio. https://www.kenwood.eu/files/file/comms/uk/brochures/nx/TK-D200_D300_V4.1.pdf Then just a day ago a seller on eBay has a complete kit, radio, battery pack, charger base, antenna etc., all NEW for a TK-5320 FM/P25 radio with the 400MHz to 470MHz band split. https://www.ebay.com/itm/275450179209?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=sUiBWWytRDK&sssrc=2047675&ssuid=j_t98fioS_6&widget_ver=artemis&media=COPY https://comms.kenwood.com/common/pdf/download/TK-5220_5320_Specsheet.pdf The price was $250 total with free shipping. Knowing what stupid high prices used P25 radios run I purchased one, the price was way too good. That gives me three of these in my collection now. Still looking for a second VHF version, TK-5220, that the seller isn't trying to rape you on price. The VHF stuff sells for significantly more than the UHF gear.

To be clear, I was absolutely not dissing Bird (I own one and love it). My point was regarding the OP's comment about 1.00:1 vswr. Specifically, even a Bird meter will almost always display some reflected power even while on a dummy load. There is always some margin/percentage of error with any measurement even with the best test equipment, ergo, always question a 'perfect reading'. :-)

Find a local 2 way radio shop. They should be able to do it on a VNA in less than an hours labor. Yes you will spend about the same as you paid for it but it will be done correctly.

That's really the why: I don't have a way of identifying what frequency the scanner was on when the recorder captured some output unattended. So it's just easier in my case to focus on one frequency at a time, and let it take however long I feel like leaving it running unattended.

Oh, the 30 seconds delay... ? LOL, way to overthink a simplest thing.

same thing in the commercial world. Difference being that anything out of the box "should" be checked before it goes out the door. I can site many examples of things like this. Big M SLR programed power 55W- reality 49.5-50 on a calibrated Bird watt meter into a calibrated service monitor. Kenwood mobiles out of the box are for the most part pretty on but do require minor tuning depending on Freq, generally the higher you go the lower the power. AT 450 you might get 48-49 but T-band 42-45 just as an example.

I'm not so sure of the reception ability of the D878UV design. I had my first generation D878 sitting on a desk next to my Kenwood TK-D340U. https://comms.kenwood.com/common/pdf/download/DMR_TK-D240V_D340U_K_letter_1124.pdf Both were monitoring the output of a local DMR repeater. On multiple occasions the Kenwood would decode audio while the D878 just light up the green RX LED and nothing was decoded. I'm doubting the ability of the D878 to reliability decode DMR traffic now. The best feature of the D878 however is the digital monitor mode. You have no idea what slot, color code, talk group and user ID is being used, well the digital monitor mode shows it all. Unfortunately the higher end commercial DMR radios can't do it. I have a MARS/CAP modded TK-D74A. The radio is a beast. It's the fastest scanning radio I have, something like over 20 plus channels per second. I've only used mine maybe a few times. Other than the D578 it's the only other radio I have than can run digital voice on the 1.25 meter band. With the prices these are selling for used it's like own a brick of gold. One odd thing is nobody in North American sold a soft case for it. I even contacted the US based Kenwood tech support and they confirmed it. Nobody could explain why. I had to order one from a Ham radio dealer in the UK and shipped it by airmail here.

Wow! Appreciate the quick response. To answer your question: I have not made it to that step yet. I have the coax (LMR 400 coax) run up to the chimney through the ridge vent and the end is capped off until I get my straps in for mounting. I did not wat to hit transmit until I get the antenna connected. The straps are due in tomorrow so I can report back this weekend. Yea started of with this radio to do some testing and if all goes well this unit it will be replaced. If it can break through this jungle (120% Humidity ;} atmosphere in Louisiana, I will be happy. Many Thanks,

Most likely. Were they the same or different values? Do they match the table of tones available on the radio. Also, make sure you are using a channel configured for repeaters (+5MHz offset -- so transmit on 467.xxxx, receive on 462.xxxx). For initial testing, just set the radio to send (encode) the tone, leave receive (decode) to None. After confirmation, you can try adding the receive tone (this may be useful if you are getting a lot of kids with FRS radios transmitting on the same 462.xxxx frequencies -- you won't be hearing them, though if close by they could still block repeater traffic).

Recently promoted from Youtube hobo to Youtube vagabond.

For more information go to YouTube and do a search for NotaRubicon. I think you will find what you are looking for. He is some hobo that has a lot of videos, many dealing with that type of radio. You will occasionally find him on a GMRS forum. He seems like an alright guy no matter what Some People may say...