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Lscott

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Everything posted by Lscott

  1. Here is some material to look over. Lightning Protection Grounding Solutions for Communication Sites.pdf Grounding Tips for the Shack.pdf
  2. Short answer most likely yes, with a duplexer. For more info on repeater building go to the link below. https://www.repeater-builder.com/rbtip/index.html
  3. I paid $400 for the radio. I seriously doubt Kenwood hasn’t included software development cost in that. They also charge for feature licensing too. That I understand. I specifically paid to have the DMR function enabled when I purchased the radio. The price was reasonable. I’m also considering getting the ARC4 encryption feature too. That involves screwing around with Kenwood’s license management software, which just so happens to ALSO requires a license key to enable!!! It uses the same Internet based licensed server BS the radio programming software requires. Gee? Really? Fortunately the license keys are free, and are targeted for dealer’s use. Kenwood doesn’t want users to be upgrading their radios either. I had a Ham radio friendly dealer send me a license manager key good for 10 installs. He also will sell the feature license keys to the radio user too. I got a quote on what those would cost.
  4. I guess you didn't read my post carefully enough. It's not the cost that's an issue, it's the usability. I've read about too many horror stories where people have paid their money, had a hard drive crash and lost the software and no means to deactivate the license since that required a functioning hard drive. Apparently this even happen to one person and it was the radio programming software that crashed and somehow wiped out the license authorization. Trying to get Kenwood to reissue a license or simply deactivate it on their end was nearly impossible and for some it was. They had to spend another $150 more or less to get their software to work again. The hassle and expense is entirely due to Kenwood's licensing. I'm not going to deal with that. If all they were worried about was recouping their cost for development then just roll it into the cost of the radios sold and give the programming software away. They do it for the Ham stuff. However this isn't their goal. What they want to do is force end users to their dealer network for tech support and radio programming. Makes the dealers happy, more business means more money for them. In fact some unscrupulous dealers will program radios with read and write passwords and keep those secret knowing that if the owner of those radios ever got the programming software there would be noway they could make changes to the programming. Of course somebody will point out it's to prevent the owner from unauthorized changes, well they own the radio, it's their license, they screw up it's their fine to pay the FCC. The dealer is not an enforcement arm of the FCC. There are other forums where it's a frequent occurrence for people to ask for software cracks/patches/engineering keys to remove these passwords. Myself I ended up with several used radios in just this condition. In one case I spent over a month searching for a patched version of the programming software to unlock the radio. I ended up buying it from a source in Mexico of all places.
  5. I've read comments where experienced radio tech's strongly recommend to stay away from Nickel or Chrome plated connectors and use only Silver plated type. The claim made is a film will form on the surface which has some rectification properties like a diode. The partly rectified RF is rich in harmonics causing all sorts of issues on RX and TX. I've also read about harmonic problems being traced to plain old rust on antenna towers for the same reason. The last bit was used to advantage during WWII for the Foxhole Radios. The blue coating on the razor blade is really a type of iron oxide coating. https://en.wikipedia.org/wiki/Foxhole_radio
  6. Lesson number one. Research the radio before you spend your money!!! That means does it have the features you want? Do you just want the radio for GMRS or does it need to cover the Ham UHF band too? Can you buy replacement battery packs for it, are chargers available, can you get the programming software and cables? If it breaks can you get it repaired and at what expense? Are accessories like antennas, belt clips, external speaker microphones available? And finally can you get copies of the documentation for the radio like user manuals and service manuals? For some people they want a radio that is FCC certified to operate on GMRS. Not all radios that can be programmed for GMRS have that. That requires checking the FCC ID on the radio in the FCC's database to check which "Parts" it has been certified to operate under. Some have the required Part 95 certification, most have at least Part 90 which is only good for the commercial frequency band. However many people use Part 90 radios, and so far the FCC doesn't seem to bother them, but it's not a guarantee. For example I'm mainly a Kenwood radio guy, nothing wrong with Motorola I have a few XPR6550's, and some cheap Chinese radios, but Kenwood is what I prefer. https://forums.mygmrs.com/gallery/image/261-e451d5e2-f358-40dd-95a1-af106f7e8584jpeg/ Kenwood has a new series of commercial radios out, NX-1000's, NX-3000's and NX-5000's. All very nice radios. The kicker is the programming software. It requires an Internet connection to their license server, the software is locked to one PC at a time, unless you deactivate it and transfer the license. Then there is the hassle of getting the software. Kenwood is targeting the programming and support to their dealer network. Trying to find a dealer that will sell you the software and license, which is $155 a pop, isn't easy unless you "know somebody" and there are a few out there. Due to the software licensing issue I had ZERO interest in looking at new or used models of the above. That is until somebody cracked the software for the NX-1000 series. Now I have one because I can get the software and installed it on several computers I use without the licensing crap to deal with. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/
  7. Wait until they setup shop on your favorite repeater's output frequency and the kids are only a few houses away.
  8. That's half duplex operation. Using two separate radios it's possible. For GMRS the mobile "receiver" radio would be set to one of the simplex channels. The audio output would be connected to the higher power mobile radio set to transmit on the remote repeater's input frequency. As you mentioned the output of the remote repeater would be received directly by the handheld radio. The handheld radio must have ability to be programmed for arbitrary split frequency operation. May of the GMRS specific radios have the frequency split "built in" and only setup for the main repeater channels, which won't work in this case. You would still need a cavity duplex type filter the same as any other repeater. There are low power ones that would likely work and are tuned by the supplier at purchase. One would end up paying around $100 to $150 depending on model. https://www.409shop.com/409shop_auctionsearch1.php?userid=100556 Also some type of "controller" would be required to couple the audio from one radio to the other and key it up. One of the Surecom models would likely work. https://www.409shop.com/409shop_shopcat.php?&usercat=4934&parentid=4934 The advantage to the half duplex idea, if the owner is the only one using it, no ID is required. Every time the handheld radio user ID's the mobile transmitter ID's too. This would NOT be true if it was a full duplex system communicating with a remote repeater. The last point is one of the major issues with full duplex mobile repeaters. It's also a sticking point for Hams using full duplex cross band repeat mode on their mobile radio, which typically don't have a self ID function. Many do it, but it's not strictly legal.
  9. For those that want a PDF version see attached file. DPL _ DCS Squelch System.pdf
  10. Is that repeater going to be moved to another site?
  11. Thanks for the link. It was a long but very detailed explanation of DCS codes. I’ll have to print it to a PDF file and save it in my electronic document library.
  12. That's about what I just paid for a NX-1300AUK5 with the DMR feature license added to it. It's now effectively an NX-1300DUK5. All the vendor had in stock were the analog only versions so I got the DMR upgrade feature license, which was fairly cheap. I don't need the NXDN feature license since I have a good collection of NX-200's and NX-300's already. https://forums.mygmrs.com/gallery/image/290-nx-1300duk5/ I'm thinking about spending the $40 more or less to get the ARC4 enhanced encryption feature license, only good for DMR. That would make the radio so it's comparable with Motorola radios using the basic encryption also on DMR. The basic model might be more along the lines of what they need. It seems that's the most popular model since it's cheaper.
  13. IMHO I think that has more to do with more spectrum is available on UHF. Using VHF for a link would use up more of the limited VHF spectrum for repeaters.
  14. The new Kenwood NX-1300’s would likely be of interest to your company. NX-1200_1300 Num 2.pdf
  15. I believe it. One might find used ones for sale on various auction sites, maybe even NOS, new old stock, for a reasonable price.
  16. You also see small ones at the top of some communications towers. They are angled at about 45 degrees. The antenna is at the base of the tower pointing up at the reflector. Some people call these “periscope antennas”.
  17. More info on passive repeaters. Passive Repeater.pdf
  18. A different MPPT controller brand might be better RF noise wise. The one I linked to the manufacture claims it doesn't generate the RF hash others do.
  19. That's possible. There are such things as passive repeaters, nothing more than a huge sheet of metal acting as a reflector. The mountains could be doing that. What might be more likely is some diffraction effects. Light waves, and RF waves, will experience diffraction when passing a sharp edge. In your case it could be the ridge at the top of the mountain. Enough energy diffracted downward to make communication possible. Warning only math geeks should try to read this. https://apps.dtic.mil/sti/pdfs/AD0117276.pdf This isn't as bad and the illustrations make the explanations easier to understand. https://www.ihe.kit.edu/img/studium/Wave_Propagation.pdf
  20. I think that's the replacement for the old -42WD type. KMC-42WD.pdf
  21. A similar speaker mic is the KMC-17. I have a couple of those and my buddy says it sounds good on the air. It might also be cheaper than the -45. KMC-45.pdf KMC-17 Revised.pdf
  22. Well it's the difference between a 1/4 wave long antenna verses a 1/2 wave long antenna. The minimum length antenna to radiate RF is a 1/2 wave length long by theory. Since a 1/4 wave length antenna is "missing" the other part, the absent 1/4 wave length, it has to be made up for some how. That's where the ground plane comes in, it doubles the antenna length so it looks like it's a 1/2 wave length long to the transmitter. To make the idea simple to understand place your finger against a mirror so it's perpendicular to it. You'll see immediately the reflection of your finger touching the end of your real one. That's basically what the ground plane does for a 1/4 antenna, it "mirrors" the other half of the antenna so it looks like it's really a 1/2 wave length long. With a 1/2 wave length antenna you have a choice where to attach the coax cable, in the middle or at one of the two ends. If the coax is attached in the middle the impedance is around 70 to 75 ohms more or less. That's a reasonably good match to a 50 ohm coax resulting in an SWR of about 1.5:1, which all most all radios will have no issues with it. For a vertical antenna the most convenient place is on the end. For some complicated reasons the impedance is far higher than the 50 ohm coax cable. For those antennas a matching section in built into the base. An example is the common "J-Pole" antenna. It's really a 1/2 wave length antenna with a 1/4 wave parallel transmission line matching section on the end. The feed point is selected such that the ratio between the voltage and current is 50, which is the required value for the 50 ohm coax. If the coax feed point was exactly on the shorted end the voltage would be zero, resistance = voltage/current, so the impedance would be zero. At the other end the current is nearly zero, the un-terminated end of the one element, thus the impedance is extremely high. Thus the match point must lie someplace between those two points. This is about as simple of an explanation without getting deeper into the theory.
  23. Have you considered swapping out the simple PWM charge controller for a MPPT type? In theory it should allow you to capture more energy and store it in the battery. With large changes in solar radiance and panel temperatures this will make a noticeable improvement IMHO. These controllers seem to work rather well. For about 100 watts of panel power a 10 amp controller would be right for your application. https://sunforgellc.com/product/gv-10/ Which solar charge controller PWM-or-MPPT.pdf
  24. From the album: Misc. Radio Gear

    This is the remote speaker microphone for the later models of the Anytone D578 mobile radios. It will control the radio over a Bluetooth link or through a wired connection. I had this one on order for almost 3 months. Due to chip shortages that's how long it took to get it. Now I have to update the firmware in the radio and load up a test code plug. Most of the settings are imported from the hand held D878 radio so that saved a HUGE amount of time building a code plug from scratch. These radios can be rather complex to program due to all the features they have. https://www.anytone.net/video/products-detail-935200 The mobile radio I have is the latest version of the D578. All though its is shown as a dual band radio with a change of the mode number in the programming software, for the US market, it will operate on the Ham 1.25M band in analog and digital modes. https://www.miklor.com/D578/ https://www.anytone.net/video/products-detail-935389 https://www.bridgecomsystems.com/products/anytone-at-d578uviii-plus-tri-band-amateur-dmr-mobile-radio
  25. This is likely the same radio but with different firmware. https://www.miklor.com/COM/Review_GMRS-50V2.php https://www.miklor.com/COM/Review_50X2.php The problem with most of the cheaper Chinese radios is the receiver section. They get de-sensed easy in strong RF environments and the selectivity can be poor. Most radio users after a while will understand the receiver is what really counts. Given a choice between more power or a bullet proof receiver I would go with the better receiver.
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