Help me with My interest in Ham Radio

Options
13»

Comments

  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    Neil thank you for the info I had not really set my mind to bands for that dipole just liked the idea of multiple bands on one antenna. I haven't tried any DX on HF yet I did chat with a fellow in Florida.

    That is good to know about the dipole I would have done it all wrong then as I would have assumed the wire would head the direction of communication. I had thoughts of putting my Shack in my office space in my garage but when I park my truck neer the garage I get a lot of extra noise on 20 meters. Maybe a taller antenna would clear that up I will experiment with the solar equipment to to see what is causing it but it is not the charge controllers I shut them all down. Maybe the Magnum inverter I know they used to interfere with analog tv.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    if it's not the inverter then a modem as they are rich with rf.
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    well I have in the garage power system the following:
    APRS World Data loggers but they are wired not wireless
    APRS World Magnum Tap again wired to the router
    Linksys wireless G router
    2 Classic controllers
    FM 60 controller
    XW controller
    2 C40 dump load controllers
    Magnum inverter

    I will do some playing when I get 5 minutes and shut one thing down at a time and see what is the worse offender.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    nothing like starting into the hobby by rfi hunting.:cry:
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    yeah I may just set my Ham shack up in my house that will cure it the noise only seems to appear within 6-8ft of my garage and does not bother 2 meter at all. The garage has a metal roof so maybe it is radiating the noise? I have used the 2 meter band with the truck in the garage with no problems.

    Lots to think about and I also have to add in the wife acceptance factor in deciding if the ham shack can be in the house. She may not want me to set up in the living room
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    i hear you on that one as that can interfere with her hearing the tv or stereo if that's where you keep them. of course you can use headphones, but that won't eliminate her hearing you talk. then again if the phone is there then you had to put up with talking from her. in a den or a nook in the bedroom is sometimes good. bedroom is only good if she's not sleeping or reading though.
    providing the interference is eliminated, i might add that your garage may be a good isolated spot to go to, but would it suffice in the winter?
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    Well my garage is kept 55 and my office has electric heat and I can warm it up to 70 in no time it is 8 by 8 I have attached a photo of it in use.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    hopefully you can address the interference there as that looks almost ideal. gee, i wonder who that might be in the pick.:confused::roll::roll::p
    edit to add: i do know who it is for the record. it's that guy from washington, ac.
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    Ok I pulled the truck into the garage today and had the radio on the 20 meter band so I could here the noise real well and went to work. Here is where it gets interesting I found 3 things that make a lot of noise but shutting one off does not help if that makes sense? All 3 items make the same amount of noise.

    So I am happy to report the following Items seemed to make no difference at all:
    Classic controllers Wind and Solar
    XW MPPT
    APRS World Data Loggers
    C40 controller

    And a little unhappy to report that the following items make noise:
    FM60
    Magnum Inverter
    Linksys wireless router or my wireless internet but I am pretty confident it is the router


    I was a little shocked the FM60 was so noisy
  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio
    halfcrazy wrote: »

    I was a little shocked the FM60 was so noisy


    Stick your tongue on the PV input and I bet you'll be even MORE shocked !
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    i think the router will need a grounded faraday cage in addition to the toroids. the other items may also need a bit more research if it's radiating on the input side or output side.
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    Yeah I will look into it I may move the router in the house I assume it is the wireless part making the noise. the inverter may be getting replaced with an xw and the MF60 will be decomishened once the Classic beta testing is done. but when I get to building up my Ham Shack I will work harder towards the noise.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    Options
    Re: Help me with My interest in Ham Radio

    Unless your HAM band is very near the wireless band (the Wifi are in industrial/unregulated bands and should not be transmitting on your HAM frequencies)--your router problem is probably the case, i/o cabling, or possibly the power cord... (yea, that was helpful--wasn't it).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    well my real question would be if I had a real HF antenna or Di Pole set up away from the garage a bit would the radio be ok? My thoughts now are the Radio's antenna is picking up the noise not the radio does that make any sense?
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    perfect sense to me. you attack it in many ways though. first is to try to reduce or eliminate the source of it and on the other side of the coin your try to reduce or eliminate it at the radio. moving the interfering source and antenna away from one another is one way of reducing it if it is being sent out over the air, but if any is being sent via the wires that is a filtering problem.

    bb,
    there is a ham band around 2.4ghz, but that's not one of the ones he's worried about. in fact most ham bands seem to take the brunt of many devices be they fcc part b compliant or not. the modems from what i have seen are general broadcasters with spikes up and down the radio spectrum. how they are able to spit out that much junk and be legal is beyond me. it may not be just enough to move the modem/router further away.
  • AntronX
    AntronX Solar Expert Posts: 462 ✭✭
    Options
    Re: Help me with My interest in Ham Radio
    halfcrazy wrote: »
    I assume it is the wireless part making the noise.

    If by the wireless part you mean actual 2.4 Ghz transmitter, then no. What's making noise on HF bands is a crystal oscillator used to set clock frequency of micro processor inside Wi-Fi router. They are usually operating anywhere between 2 and 50 Mhz. Placing the router into grounded metal box should fix that issue. Using shielded cat-5 cables and grounding the shield should help too.

    I recently have built little tiny tracking transmitter to place on my cat's collar. It uses one of those popular crystal resonators used in every computer out there. The crystal is 49.152 Mhz device, giving me a signal on 147.460 Mhz on it's 3-rd overtone. The problem is, my cordless phone, two computers, dsl modem, LCD TV, alarm system all radiate a signal on that same frequency. That makes my 2 meter radio unusable on that frequency inside my house.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    i'll back up antronx on that it isn't the 2.4ghz transmitter doing this.

    antronx,
    i think you might be able to slide that oscillator's frequency a bit by adding some capacitance across the crystal. not sure how much it'll need or if it's even applicable to that oscillator, but might be worth a try if there are spikes like those i see here.
    if that's no good consider monitoring it for its 49mhz frequency. the antenna would be a pain though.
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Options
    Re: Help me with My interest in Ham Radio

    We are awash in RF EMR. The way of the world. How many of the "unwashed" even know that there are FCC allocations.

    My great uncle, Arlo Eggensperger, was a HAM. b. ~1910, d, ~2000. Had some articles published in the ARRL magazine. He worked for what was then AT&T. Supervised land line comms for NASAs Mercury missions. I once visited his shack in NJ ca. 1970. Gave me lots of parts. Simple things. Switches & meters. Best was the Triplett 350? multimeter.

    I might get into this hobby someday.

    Craig
  • AntronX
    AntronX Solar Expert Posts: 462 ✭✭
    Options
    Re: Help me with My interest in Ham Radio
    niel wrote: »
    i think you might be able to slide that oscillator's frequency a bit by adding some capacitance across the crystal...
    ...consider monitoring it for its 49mhz frequency.

    I tried 2-30 pF trim capacitor parallel to crystal, that kills whole oscillation, so that does not work. What works is placing it in series with crystal, but it can only shift the frequency up by about 10 Khz, that's not enough. Bigger caps have no effect. Then I placed a coil in parallel with trim cap and things really changed. I was now able to tune down by few Mega Hertz! The problem was now the frequency drift from touching the circuit. Another problem was, the transmitter was now sweeping the band instead of just keying up on one frequency. It would key up on 147.400 and un key at 147.450 Mhz.

    Monitoring 49 Mhz would not work either. The transmitter radiates about -40 dBm below the 147 Mhz carrier on 49. That is largely caused by the antenna only being 3 inches long wrapped around cat's neck (well, that sounded cruel, but the antenna wire is sewn to the collar, not the cat...) Then there are 4th, 5th, 6th 7th 8th 9th overtone carriers, but they are attenuated as well.

    Overall, the transmitter is still very useful in locating the feline. Range on the HT radio is 3 - 5 houses or 300 feet in the open. Range on the mobile is considerably more. Battery life is 37 days calculated.

    I am trying UHF SAW resonators now in 420 - 433 Mhz range used for door openers and such.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio

    sorry i miss remembered if it was across the crystal or in series.:confused::cry:
    good deal on the inductance sliding it more, but it introduced some stability problems. maybe use a toroidal coil to reduce the proximity effect? i know it's more on the cat's neck.:cry: uhf is a good option and maybe scrap the current transmitter for another up there?
    i don't like sidetracking here too much from the op so we should wrap up the oscillator discussion, but i hope it kicked some ideas up for you in getting a resolution.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    Options
    Re: Help me with My interest in Ham Radio

    Then you guys would love what us systems guys do sometimes to pass FCC regulations...

    You are allowed to use a filter to lower the apparent readings of our emmissions... Well, many times the exact processor clock frequency is not a fixed requirement... So what we do is place a VCO as the clock source and drive it with a triangle wave (if I remember correctly)--Now we have spread spectrum'ed the clock somewhat...

    More bandwidth stepped on?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Options
    Re: Help me with My interest in Ham Radio
    BB. wrote: »
    Then you guys would love what us systems guys do sometimes to pass FCC regulations...

    You are allowed to use a filter to lower the apparent readings of our emmissions... Well, many times the exact processor clock frequency is not a fixed requirement... So what we do is place a VCO as the clock source and drive it with a triangle wave (if I remember correctly)--Now we have spread spectrum'ed the clock somewhat...

    More bandwidth stepped on?

    -Bill

    So this is why when the consumer buys something that "meets FCC regulations" it still dumps a ton of noise into the stereo? :roll:

    This is a very interesting and informative thread, even if you don't find yourself dealing with RF issues. :D
  • boB
    boB Solar Expert Posts: 1,030 ✭✭✭✭
    Options
    Re: Help me with My interest in Ham Radio
    AntronX wrote: »
    I tried 2-30 pF trim capacitor parallel to crystal, that kills whole oscillation, so that does not work. What works is placing it in series with crystal, but it can only shift the frequency up by about 10 Khz, that's not enough.

    Typically, you add the capacitance from either side of the crystal to ground.
    Not in parallel or series with the crystal. This will only pull its frequency a little bit, but sometimes plenty enough. It won't pull a lot.

    The mode the crystal is running in (parallel or series) may make a difference in results.

    Many times, you can actually replace the crystal with an L-C network if you really need to vary the frequency.

    boB