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WRAK968

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WRAK968 last won the day on June 1 2021

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  • Unit Number
    101
  • Location
    Little Egg Harbor
  • Interests
    Hiking, Camping, Fishing, Radio comms, and Firefighting, Not always in that order.

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  1. Also note the SW-102 does need fine tuning against a known source like a dummy load or another meter, however at 19-1 reading even on an untuned meter isn't good.
  2. No problem. We all have life to deal with, glad the info was helpful
  3. Well, I know the rim-lite/rim-lite RM is designed for 1225 series radios as that is what I use on both the RKR1225 and GR1225. It simply plugs into the 16 pin accessory port on the radio. (You will need to open the case to access the unit inside. The 16 pin port is near the TX antenna out port.) I recommend running the USB cable out from the case so you can have better access to the pi setup, it also helps keep the pi cool this way. For the 7000, there is an accessory port on the back that you would hook up to, however I don't have any experience with this repeater and wouldn't be able to get into the technical discussions of its connections. Luckily, we have places like Repeater Builder which give us access to information like this: http://www.repeater-builder.com/yvs/vxr-7000-cat300dx.html and this: http://www.repeater-builder.com/cat-auto/cat-notes/note_11.pdf which may help
  4. I see what your getting at now, kinda interesting and I never thought of it that way
  5. I thought you wanted the notch dead on for duplexer's to prevent desense? What causes the increased insertion loss?
  6. Being new, I'll let ya know that this is how I started out as well, and... it didn't quiet end well. Motorola mobile radios are meant for a 20% duty cycle, another words, they shouldn't transmit for more than 2 minutes out of every 10 or damage will occur. When you do your set-up, I would put the TX radio on low power to protect the radio from burning up, even if you've added a fan, as it doesn't take too many long winded conversations through the repeater to cause irreversible damage. Likewise I would program in a 90 second time-out timer (TOT) on the repeater itself. I learned this the hard way as I fried a 1225 40W mobile by running longer than normal transmissions on high power, and by using an improperly tuned duplexer (Another thing, save yourself the headache and buy a BP/BR duplexer for the UHF band. They usually go for $300-500 used on ebay and in my experience work a lot better than the cheaper flat packs.) If you have any more questions feel free to call on us, theres a great set of guys here with quite the database of information
  7. tweiss3, I am using the MyGMRS asterisk controller, and am curious how you were able to add in the weather alert feature. Would you be able to go more in depth?
  8. Then there's the liability side of things. Every EAS activation over any form has to be documented, and in the event that an EAS alert is transmitted over a wide area (for instance, on linked repeaters using the national node) one could face very large penalties for creating a false public alarm. Likewise, If it is advertised that a repeater has EAS announcements, and the EAS fails to alert to an emergency you could equally be held liable. Then there's the cost. You would need a special EAS decoder for your region of coverage, a printer for the EAS message data header (required for log book), and back-up power systems (2) to ensure the system is reliable in a worst case situation. I found all this as I too planned to use EAS via radio so that I didn't have to buy dual band radio that would only TX on one band. The thinking was to give my family and I notice about bad weather while we were hiking or kayaking. After learning about all the equipment that is required, and the liability parts, I chose not to go that route and instead installed a weather app on my phone.
  9. I just know what I've been told in the past. First, I do not do anything inside of the radio, instead I use the software to make changes to the radios power output. The TK880 uses digital tuning to make said changes. However, I've found that going more than 5-10W below what the radio is rated for can cause heat buildup in the radio, limiting your TX time and risking damage to the radio. Its why I don't recommend dropping that low without a service shop doing it as they can make physical changes to the radios internals that would prevent this.
  10. You may have no choice but to shift frequencies, THOUGH, a good duplexer should be blocking out anything from 457 on the receive side of the repeater, in fact it should be blocking anything below 467.0000. The big concern with using offset frequencies is that in the end you end up blocking 2 repeater pairs. This may not be a big deal if there are no other repeaters in the area, however if you do have other repeaters, it can cause more interference issues. Another thing to point out is that a lot of pre-programmed 95E radios will not allow you to do an offset like this, meaning there will be radios which would not be able to reach your repeater. In my opinion, you may be best checking/upgrading your duplexer to block lower frequencies, and perhaps moving the repeater away from the harbor if needed.
  11. Dropping to 5 watts on a high power radio will cause damage, I honestly wouldn't even let it run at 10W as low power is rated at 25W. If you want the lower power, you may wish to get the standard 880, (Non-H version) which can handle 5W low power with little issue. The problem is that reducing the power output beyond specifications causes heat to build up in the radio, the more heat, the more likely you could burn up the finals, and yes, it can even happen with extremely low power being used. I'm not exactly sure why this happens or the science behind it, so perhaps one of the better knowledge folks could explain it for me
  12. Fair bit of questions here. Tuning is done through the KPG software for the radio, HOWEVER, I would not attempt to retune a radio without the proper meters and equipment and a surecom 102 isn't the best to meter for perfection. One thing I do question is, have you tested the meter against a known source? I do use a surecom meter myself for quick checks, and I recall that I had to tune the meter before I could use it. It took a few trys however I did get it to be close enough for what I do. IF you choose to do this yourself with cheap equipment, I am not to be responsible for damage or rule violations. You will need a length of coax about 1.5 times the frequency wavelength, (9 or 18 inches should work) the meter, a 50 ohm 100W dummy load able to support the frequency you are tuning for, radio, power supply, programming cable and computer with KPG49D software. Set up the radio and power supply, connect the coax from the radios antenna port to the "Input" side of the meter, and connect the dummy load to the "Output" side. Connect the programming cable, and turn the radio and computer on. Open the 49D software and do a read from the radio. Click "Edit>Test frequency" Enter in several frequency sets, You should have the lowest frequency you plan to transmit on, the highest frequency, and a frequency somewhere close to middle between your high and low frequencys. Save the file, and write to the radio. Once written, click "Program>Test Mode" Select the center frequency (likely to give you the best results for your usage "band") Double click "RF High Power" Take a note of the current value, Just in case you make a mistake, you're able to return to this number and start again. Use the left and right arrow to adjust the value in the new window. Make small adjustments and click "TX" Get a reading and click "TX" again to stop transmitting. Keep making adjustments until you reach about 40W (This unit is rated at 40W output to my knowledge) You can run slightly low, however to protect the radio, I wouldn't tune above 40W. Once complete click "OK" to exit to the test mode window. Select the lower frequency and go back into RF High Power, DO NOT MAKE CHANGES, Simple click TX and take a reading, and do the same for the High frequency. Note, Both frequencies will be BELOW the 40W output. This is NORMAL as long as they aren't super low. When complete, click "Close" in the test mode window, and your radio should reboot. For low power, I don't believe that radio can go much further than 20W low power without causing damage to the radio, and for frequency alignment and getting into the 70CM band you would likely do better taking the radio to a shop and having a pro do it for $50. This will void the part 95 certification, however at least there is less risk of transmitting way off frequency by accident. I would also advise against any physical adjustments on the radios boards as a 1/4 turn on the wrong pot will fry your radio, your station, or worse, could cause a fire. Again, most shops can preform this service at a reasonable price for you.
  13. Well, if there are no linked repeaters in your area, try looking for a linked repeater with Zello connections. (Bronx broadnet/bronx zoo comes to mind) On Sunday nights there are regional nets held, and once a month a national net. You would need to use a PC or phone to connect, however its a start.
  14. I suspect the 76D is older software that was transitioned to windows from older styled DOS programming. If this is the case, chances are the program will only allow you to access one of 4 com ports, which back in the DOS days (before USB) was the common number of ports Well, before anything we need to figure out what com port number the programming cable has. Open the start menu and type "Device Manager" and it should locate device manager in control panel. Open it. Under Ports (COM & LPT) you should find your cable with (COM#) next to the name. Typically using a serial device this would be COM 2. However because we are using USB here, the computer gives it its own COM # and I've seen it go anywhere between 3 and 8. If your COM port number is greater than 4, don't fret, I believe there is a way to fix it. In device manager, right click on your cable under ports & coms, and click "Properties" In the new window click on the "Port Settings" tab, then click "Advanced" Where it says "COM Port Number" Change to Com3 or Com4 (Com 1&2 are usually used by your motherboard for other applications and may cause signaling issues. Also important, anything using Com 3 or 4 will likely need to be moved if it is in use.) Click "Ok" and the window will close, Click "Ok" again in the previous window and it too will close. Check that the cable comes up as COM3 or 4 in device manager. If it does, restart the KPG76D software, and try to select the port. It should be open now. If it still will not let you select the port, you may need a serial cable and capable computer to program. I know some radios and programs are a bit glitchy like that. Let me know how you make out and if you have any questions.
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