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  • brandon lind's Avatar
    Yesterday, 17:46
    You might want to consider a different antenna before you fly it. A half wave MONO pole is ANTI-resonant. If you have the space for a half wave, why not a DIpole? You can incorporate one quarter wave element into the balloon-to-payload tether and the other quarter wave element hanging below. Maybe that infinite SWR is shutting down the transmitter immediately through a protection circuit....
    2 replies | 60 view(s)
  • 5B4AJB's Avatar
    Yesterday, 13:46
    Do you have the packet baudrate set to 1200? sounds like you may have it set to 9600...
    2 replies | 60 view(s)
  • spbrhs07's Avatar
    Yesterday, 08:23
    I am working on a weather balloon project and I'm trying to figure out my GPS transmitter. I'm using a Radiometrix HX1 radio module with an Arduino Uno 9v, 1A power supply. At this point it's all plugged into a breadboard as I'm still testing everything. For the antenna I'm using a 1/2 wave monopole whip. The antenna is connected to an SMA connector soldered to a PCB with soldered jumper wires going to the antenna pins on the HX1. Here is a picture of what I've put together, minus the temperature sensors and the buzzer... https://cdn.sparkfun.com/assets/learn_tutorials/7/8/1/trackuino_fritzing1.png If anyone's curious about the code, it can be found here... https://github.com/sparkfun/SparkFun_Trackuino Everything complies and uploads fine to the Arduino. The GPS locks to multiple satellites and it appears to transmit fine.
    2 replies | 60 view(s)
  • brandon lind's Avatar
    Yesterday, 07:37
    brandon lind replied to a thread Base Radios IC-745 No RF output in Icom
    I am very confused... Let’s start with the known facts. You measured 8.04v at the + side of C21 (which also happens to be directly connected to the higher side of R29). You measured 7.61v between R29 and R3. This gives a voltage drop across R29 of 0.43v. Using ohms law, we can determine the current through R29 as being (.43/10ohm) = 43mA. The manual calls for 0.4v at the emitter of Q1 (you measured 0.180v). Since the emitter resistor is 2.2ohm, we should expect an emitter current of 0.4/2.2 = 182mA. Given a beta of 144 (you measured), there should be a current of 182mA/144 = 1.264mA at the base. Generally, a voltage divider type bias for a class A amplifier is designed to have at least 10X the current through it to stabilize the voltage at the base. Being the voltage divider is comprised of R3 and R2, and knowing R3 has the same current flow as R29, we know we are well within spec at 43mA for the divider circuit. Knowing we have 3.4X more than the suggested current through the divider (R3 and R2), it...
    12 replies | 419 view(s)
  • Dale Paul's Avatar
    Yesterday, 01:59
    Dale Paul replied to a thread Base Radios IC-745 No RF output in Icom
    Brandon. I’ve ohmed R20, I don’t have a precision ohm meter so the reading I got was 0.1 ohm. The svc manual IDs it at 0.012 ohm and 5 watts. All transistors were replaced with OEM Mitsubishi parts, and matched pairs for the drivers and PAs. I checked Beta for each transistor before installing them and they were all good. Using my transistor tester I find the Hfe/Beta Q1 is 144, Q2 is 72, Q3 is 78, Q4 is 83, Q5 is 82. After I replaced Q1 (for the 3rd time) I ohm checked all transistor leads for good solder connection. I removed R23/R27 and ohmed them also, R23 was 435 ohms and R27 was 90.5 ohms. As I said earlier Q1 has been replaced twice before in trying to fix this problem. I have 7.61Vdc between R29 and R3, 180mV at the Q1 emitter when the mike is keyed. With an amp meter in series with W35 and W10 and the mike keyed, I get 3mA and adjusting R23/R27 show no increase or decrease.
    12 replies | 419 view(s)
  • Teslas_Understudy's Avatar
    Mon 14th Jan 2019, 23:27
    Hello everyone, I am joining in an effort to learn about amateur radio and hopefully get the basic license this year. Take care, and I look forward to doing lots of reading here! Sean.
    0 replies | 48 view(s)
  • mi5utc's Avatar
    Mon 14th Jan 2019, 22:42
    Came across this forum as I have similar problems with my TR9000 and was wondering if anyone had successfully resolved this matter ? I am wondering if the mode switch has something to do with it, maybe oxidisation creating a poor contact. Iíve had the PA replaced with a rare to find new one and radio puts out a very healthy 13w but the sudden drop in rf output still shows up from time to time. I flicked the mode switch about and the radio worked perfectly so Iím thinking a good clean if possible or a replacement if one could be found. I would take the switch out of curcuit in favour of permanent USB but I still dabble on FM. Any more advice or results out there ?
    6 replies | 8161 view(s)
  • doc_cj's Avatar
    Mon 14th Jan 2019, 15:36
    Hello all ... I am taking the Technician (and hopefully General) exams on Saturday, 01/19/19. So, as you can see, I am still a very new newbie, not only to this forum but to Ham Radio as an avocation. Here's just a bit about me to get me started on this forum. I'm in my sevent decade on this planet and recently retired. Over my career I spent 10+ years in law enforcement, 9 years as a private attorney, and then got into academia for an 18 year tenure run as a Professor. I hold the Juris Doctor (J.D.) and Doctor of Philosophy (Ph.D.) degrees. I am the author of a dozen books and more than thirty journal articles in academic (peer-reviewed) and professional journals. My interest in Ham goes back to the days when I was a kid and my Dad was into CB and eventualy Ham. This would have been in the early '70s. I used to spend many nights with him in his shack while he worked on repairing radios for friends and for a small fee. For some reason, though, I didn't get into the electronics aspect of the...
    0 replies | 29 view(s)
  • Richard Harries's Avatar
    Mon 14th Jan 2019, 11:20
    I've had a radio license for about 30 years but I haven't used it for a very long time, therefore I'm a bit ignorant about modern practice. I'll be rowing across the Atlantic in 2020 and I'm wondering if it is a practical option to use shortwave as a means of communication. I'd be very grateful if anyone with experience of using SW on an ocean could respond. Thank you.
    0 replies | 26 view(s)
  • paulears's Avatar
    Mon 14th Jan 2019, 10:27
    paulears replied to a thread Calculate Offset in Activity Forum
    The tyt th9000d we buy in the UK is TX/RX up to 174MHz. Is the US version limited to ham bands only? I'd also check that 168.495MHz frequency. 5KHz spacing is a new one for me on repeater splits - they're usually fairly big whole numbers - and if the TX ends in a '5' then the RX normally does too - 4.02Mhz is a very weird split even 4.025MHz, which is a 12.5KHz channelisation would be a bit strange - at least in the UK.
    4 replies | 116 view(s)
  • K7KBN's Avatar
    Mon 14th Jan 2019, 06:01
    K7KBN replied to a thread Calculate Offset in Activity Forum
    If you're required to use a radio as a condition of employment, the employer is generally required to furnish a legal, certificated radio to all such employees. The technician is absolutely right not to attempt to make a radio something it was never intended to be. What kind of radios do the other employees use?
    4 replies | 116 view(s)
  • brandon lind's Avatar
    Sun 13th Jan 2019, 22:01
    For the sake of the thread name.... you have your offset sign wrong. If the repeater TRANSMITS at 168, you RECEIVE on 168. That means you must transmit on 164, the repeater INPUT. Typically, radios denote offset direction from the receive frequency thus giving you a NEGATIVE offset, not +. As for whether or not that radio can TX out of the ham bands, no clue. i don't own one. I am in agreement with 5B4AJB regarding the likely necessity of a modification to make that happen. If you already modded it, make the offset -4.020 73!
    4 replies | 116 view(s)
  • 5B4AJB's Avatar
    Sun 13th Jan 2019, 20:38
    5B4AJB replied to a thread Calculate Offset in Activity Forum
    I two words - you can't. Unless you find a broadband transmit mod for the radio...
    4 replies | 116 view(s)
  • mess's Avatar
    Sun 13th Jan 2019, 17:24
    mess started a thread Calculate Offset in Activity Forum
    Hi guys, I'm new in here and would appreciate a little help or guidance. I have one of those tyt th9000d 2m radio. My issue is trying to figure the out the offset. Most repeater I have seen have a + or -600 for an offset but this one is for my work radio. The technician said he won't touch Chinese radios so I'm left with no radio. So correct me if I'm wrong, the repeater recieves on 164.475 and transmits on 168.495....I have the offset calculated to +4.020 . And the tone is 218.1 . Does any of this make sense? Thanks for any advise.
    4 replies | 116 view(s)
  • brandon lind's Avatar
    Sat 12th Jan 2019, 02:59
    brandon lind replied to a thread Base Radios IC-745 No RF output in Icom
    A closer look at the board confirms there would not be voltage on R20 with jumper W10 removed. I didn't realize R20 was AFTER the jumper as the schematic did not depict its location, no worries there. But ohm out R20 just for fun... Otherwise, those voltages look close but a bit low. Again, I am assuming the transistors you installed are identical replacements or suitable equivalents and are in working order AND installed correctly. The R23 and R27 pots, when adjusted, should give a current through the removed jumpers. Forgive me for asking, but are you making sure the ammeter is in DC mode and not AC mode and BOTH the probe tips each connect to where the W jumper ends were soldered in (using the ammeter as a jumper unlike a voltage measurement with the black probe to ground somewhere)? If done right, based on those measurements only 4 possibilities should remain: 1) the transistors have a much lower beta than the originals and the bias resistors need changing to different values, 2) the transistors...
    12 replies | 419 view(s)
  • Dale Paul's Avatar
    Fri 11th Jan 2019, 18:38
    Dale Paul replied to a thread Base Radios IC-745 No RF output in Icom
    Brandon, here are the results: There is 8.04vDC at the + side of C21 There is 1.31vDC at the anode of D2 There is .53vDC at the anode of D1 There is no voltage at R20, I removed the bare wire at W10. However there is 14.5vDC on that bare wire. I discount any small voltage differences are a result of my DVM error rate.
    12 replies | 419 view(s)
  • AC5PS's Avatar
    Fri 11th Jan 2019, 17:06
    I have two, it’s a good HT and also has C4FM. The only thing I don’t like is you have to use two hands to adjust the volume.
    2 replies | 154 view(s)
  • paulears's Avatar
    Fri 11th Jan 2019, 12:15
    The Yaesu, based on previous products will still be working in 20 years time. The Baofengs are disposable. If you break it, you buy a new one. Yaesu will keep spares, and give you support. In real terms, the differences are in development and time spent on the user experience. Toughness, build quality - that kind off thing - NOT TX or RX performance, with the small exception of the ability to reject unwanted signals. The name brands always have better filtering!
    2 replies | 154 view(s)
  • xdm's Avatar
    Fri 11th Jan 2019, 03:17
    Okay so I currently own the Baofeng radio. I was talking on a local ham two days ago about an upgrade. I was recommended to buy the FT-70DR radio. I currently see an instant rebate on it for $149 on https://www.gigaparts.com/yaesu-ft-70dr.html?gclid=EAIaIQobChMI_v3N-eDk3wIVBIppCh2eXQ5GEAkYASABEgL4UvD_BwE. I feel like this is a steal deal. However I don't feel fully knowledged yet of all the things I can do with my baofeng but I feel purchasing this yaesu radio will make it easier to get better with ham radio. Should I jump at that deal or leave it. Also can someone give me a comparison of the two radios. How will the Yaesu radio outperform my baofeng?
    2 replies | 154 view(s)
  • K6CPO's Avatar
    Thu 10th Jan 2019, 18:43
    The FT-8900R is strictly a ham radio, operating in the 10 meter, 6 meter, 2 meter and 70 centimeter bands. It will not operate on GMRS or MURS without an illegal modification. As answered above it is illegal to use the Baofeng on GMRS. This is a viable solution, but the Midland cannot be used on the ham bands.
    3 replies | 288 view(s)
  • 30362's Avatar
    Thu 10th Jan 2019, 13:32
    Thanks Brandon, that helps. So if I read your reply correctly, even the Yaesu that was recommended, because it's a HAM radio, wouldn't be permitted on GMRS. That said, since I have the GMRS license bought and paid for, I would need something like the Midland MXT100, 105, 400 for a GMRS base radio, and some Midland handhelds for the wife and son to be 100% legal. Then if I (when I have a tech license) wanted to use HAM bands I COULD use the Baofeng, just not for GMRS, MURS, FRS etc... So basically the answer is buy more radios :) There's no way to have one for both.
    3 replies | 288 view(s)
  • Obed's Avatar
    Thu 10th Jan 2019, 12:09
    Obed replied to a thread Hello from W8GXR in Introduce yourself
    welcome to the forum, lots of nice folks here and one or two old grouches....but I do have good days too.
    1 replies | 94 view(s)
  • W8GXR's Avatar
    Thu 10th Jan 2019, 03:16
    Found this forum and thought I would join to learn, share and enjoy the art of radio Interests include: VHF Voice and Data HF Voice and Data Digital modes Shortwave Listening 73's from Cincinnati OH
    1 replies | 94 view(s)
  • brandon lind's Avatar
    Thu 10th Jan 2019, 01:32
    From a legal standpoint, you cannot use a Baofeng (or any ham radio) on FRS or GMRS as those frequencies are covered under part 95 and the Baofeng is a part 90 radio. The obvious reason for this is because even the most law abiding operator would have a hard time resisting the temptation to utilize the power capabilities of part 90 gear on GMRS/FRS frequencies. So rather than allowing part 90 radios on GMRS/FRS and attempting to enforce the power limit, they limit the radio options for part 95 to those with fixed output power, non-programmable RAM PLL circuitry, and fixed antennas. I don't know for sure, but I would suspect that an attempt by a ham to reprogram or modify a GMRS/FRS radio to work the ham bands (which would be legal on the ham bands) would disqualify it for use on GMRS/FRS. If your intentions are to operate within the confines of the law, you will need to carry 2 radios.
    3 replies | 288 view(s)
  • 30362's Avatar
    Wed 9th Jan 2019, 23:04
    Hi all, I am just getting into amateur radio, in fact one of my resolutions for 2019 is to get my technician and general licenses. So apologies for all the newbie questions. That said, I have a few questions that I'm hoping someone can help me with. if this is the wrong place my apologies, please feel free to tell me where to go :) I want to get a radio so I can get started with HAM, listening now, and transmitting WHEN I pass the tests, plus I want to be able to use handhelds. We camp, hunt and ATV in Kentucky and I want to be able to use handhelds with the wife and son while we are out playing, so I bought 3 of the $30 Baofeng UV-5R handhelds, and I've read all the nastiness about them, so I don't plan to use them until I'm legal on the HAM bands, but have some questions about those and a mobile unit. I've used FRS blister-pack radios in the past, and I have used MURS radios (don't remember the model, I know they were 95? compliant) and I would like to be able to get a mobile unit for my...
    3 replies | 288 view(s)
  • brandon lind's Avatar
    Wed 9th Jan 2019, 16:53
    brandon lind replied to a thread Remote Antenna in Antennas
    This is why I could never live in a city.... Bureaucrats you never voted for making decisions that affect your life, decisions that usually hinder ones pursuit of happiness with little benefit to society. Enjoy your hobby because the reward far outweighs the risk! Get a razor blade and cut an X in the carpet so the drill bit doesn't tear it when you drill through the floor. When you move out, nobody will ever see the hole.
    4 replies | 162 view(s)
  • brandon lind's Avatar
    Wed 9th Jan 2019, 15:24
    brandon lind replied to a thread Remote Antenna in Antennas
    Depending on the radio you have, there are some that connect to an external unit and allow for remote control through the internet (or WLAN) on a PC or smartphone. Try www.remoterig.com Another alternative would be a cross-band repeater, but you would need to go to the attic to change frequencies. A RX only option requiring nothing in the attic is to listen online to some of the radios on www.websdr.org There are many stations you can choose from all over the globe and they allow you to tune to a band, frequency, mode etc of your choice. They don't all run the best of antennas, but still fun! EDIT: City ordinances don't have control of what you attach to your vehicle, sneak the coax out from under the garage door and connect it to the car antenna. Anyone asks, its an extension cord for your block heater or battery charger. There are also a wide number of options for stealth antennas. If you are allowed a satellite dish, a slot antenna cut into the dish is effective for VHF. That would also...
    4 replies | 162 view(s)
  • Obed's Avatar
    Wed 9th Jan 2019, 12:02
    Obed replied to a thread Another new guy in Introduce yourself
    welcome to the forum. Always glad to see new folks....
    1 replies | 101 view(s)
  • K4CQO's Avatar
    Wed 9th Jan 2019, 04:24
    K4CQO replied to a thread Remote Antenna in Antennas
    Did you consider running the coax along the outside of the house. All cable / satelite companies all run the cables on the ourside of a house from the downstairs to the upstairs. I have also done it in Massashuetts without any problems. A drill hole is not very large that will fit coax thru and easily sealed and secured to the side on the house.
    4 replies | 162 view(s)
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