|
xergm posted:So I learned something new last night. I don't normally play around much on SSB, I usually stick to data mode at <25 watts. 100% same. Once I key up on 40m over 40, 50w or so my entire heater hvac tower kerchunks... And when I first tried it killed my nest thermostat. Had to replace it, so, I don't operate on 40 at present. (Ferrites not helping.)
|
#
?
Dec 21, 2015 18:41
|
|
|
|
| # ? Jun 5, 2024 01:22 |
|
|
Nest uses FETs instead of relays to switch the control lines. Apparently they're pretty easy to short out, a number of people have had them fail and start running parts of the system non-stop, sometimes resulting in damage to the HVAC system. It wouldn't surprise me to find out that's what blew in yours. Induced current from the radio comes down one or more of the control lines there we go.
|
|
#
?
Dec 21, 2015 22:17
|
|
|
Correct that is what happened. It started trying to run the a/c start relay constantly and it sounded like it was exploding, I was freaked out by it lol. All over the low voltage lines - luckily nothing died except the nest.
|
|
#
?
Dec 21, 2015 22:34
|
|
|
I might order some chokes to see if that helps. I've seen more than a few suggestions to use them so solve this, but whenever they're suggested, I fell like they're vastly overstate in their ability to solve RFI. It also caused a little bit of hum in my stereo downstairs, but that's a much smaller issue that I don't care about as much, so long as I'm not doing the same thing to my neighbors. The other suggestion was to using battery powered detectors, but both of mine already are.
|
|
#
?
Dec 21, 2015 22:47
|
|
|
I've got chokes all up and down the ends of the lvac lines to between my nest and the heating unit, still happens though. Not as bad, but not a fix. My solution is just to move the antenna. It's a doublet along my roof about 2' up the roof, and its not only above but parallel to the HVAC wiring so... I just need to move it. Thinking a Hustler 4BTV, some quickrete, calling 811 and poking down some ground plane wires into the yard, and just skip the doublet out of a G5RV jr.
|
|
#
?
Dec 22, 2015 02:33
|
|
|
wolrah posted:Nest uses FETs instead of relays to switch the control lines. Apparently they're pretty easy to short out, a number of people have had them fail and start running parts of the system non-stop, sometimes resulting in damage to the HVAC system. Sniep posted:Correct that is what happened. It started trying to run the a/c start relay constantly and it sounded like it was exploding, I was freaked out by it lol. All over the low voltage lines - luckily nothing died except the nest. Totally what happened to my Nest. I don't think it was RFI, as my shack is inside of a metal building, but it happened and it took some convincing to get them to just send me another drat base. All is well again. I heard the compressor running when poo poo was off and at first thought it was a short. Ran the lines and newp.....the nest base was bridging Y1 to C (kinda, but enough to trip the relay) even with the thermostat off of it.
|
|
#
?
Dec 22, 2015 03:29
|
|
|
Motronic posted:Totally what happened to my Nest. I don't think it was RFI, as my shack is inside of a metal building, but it happened and it took some convincing to get them to just send me another drat base. All is well again. It's messed up! I took a vid of mine when it happened on my phone, witness: https://sniep.net/AC_Misbehaving.mp4 The ending being me running back saying "gently caress this" and killing the HVAC power at the breaker box again.
|
|
#
?
Dec 22, 2015 04:49
|
|
|
Do note at this time in that video I had not yet a clue that my TX on 40m had any impact on my HVAC, that was me working backwards through the problem, and cutting the breaker to solve for it an mystified that there was a low-voltage AC line to begin with as well as the fat one. Home ownership! I'm a newb. Now I know.
|
|
#
?
Dec 22, 2015 04:54
|
|
|
Sounds like you somehow turned your HVAC unit into a spark gap transmitter.
|
|
#
?
Dec 22, 2015 04:54
|
|
|
I wonder if changing out the HVAC control wiring for twisted pair, possibly shielded, would help. I don't understand the RFI side of things well enough to know if the cable alone would help anything or if it's the way that the devices on the ends use the twisted pairs and/or ground the shielding that actually makes it beneficial where it's normally used.
|
|
#
?
Dec 22, 2015 05:04
|
|
|
xergm posted:Sounds like you somehow turned your HVAC unit into a spark gap transmitter. You jest but that is exactly how I first noticed the issue. I tried tuning up on 40 a few times, kept increasing watts, then heard my HVAC system kerchunk a time or two, then heard 10-20 seconds afterwards this super loud interference just popping in no matter where I tuned. That's about T-4 mintues from the vid I posted. lol
|
|
#
?
Dec 22, 2015 05:04
|
|
|
 WOOOOOOOOOO Just made my first out of state contact on ham radio ever. From DM79 (Denver, CO) to EN51 (Chicago, IL), 6meters @50.125, Moxon antenna on a rotator aimed roughly NE and 50w USB on the ft1200, got him crystal clear maybe S4. Hurray first real non-2m-or-above QSO!
|
|
#
?
Dec 26, 2015 05:29
|
|
|
Nice! I was messing around with JT-65 yesterday and caught a faint call from 5-land. I gave him a quick call back without looking at the grid square. Image my surprise when I look up his call on QRZ and find out he's not even 20 miles away. I didn't even leave my own grid square (EM28)  Although since my G5RV is facing N-S, and he was almost directly west, he was probably in the null of the sidelobe, which is why he was so weak.
|
|
#
?
Dec 29, 2015 22:17
|
|
|
And now my first DX contact, up in Canada DO42 to my DM79. 40w on 50.125, USB. This poo poo rules.
|
|
#
?
Jan 2, 2016 07:10
|
|
|
I am going to test for technician and general. Started out looking for something better than FRS and ended up with a KG-UV6D for GMRS and MURS. Got curious about the amateur stuff and this all sounds awesome.
|
|
#
?
Jan 6, 2016 07:58
|
|
|
Does anyone know what happened with the ARRL's symbol rate petition? All the articles I found were either simply describing the change, or people bitching by claiming it would ruin the bands for cw or rtty.
|
|
#
?
Jan 7, 2016 06:40
|
|
|
This was the latest I've found: http://www.arrl.org/news/arrl-executive-committee-presented-with-draft-enforcement-improvement-plan Sounds like it's still stuck in the FCC's court. Edit: Has anyone done anything with the club call we got a while back? We got AG0ON, but I don't think I've ever heard of anyone using it. xergm fucked around with this message at 15:23 on Jan 7, 2016 |
|
#
?
Jan 7, 2016 15:16
|
|
|
I tried a while ago, and the trustee of the club sign even popped back in here. But it went nowhere from there.
|
|
#
?
Jan 7, 2016 17:21
|
|
|
Motronic posted:I tried a while ago, and the trustee of the club sign even popped back in here. But it went nowhere from there. Trustee is still around. Hi. If people want to use the call for something they're doing, I'm just asking that you tell me what and when so I know where to redirect the OO complaints when they arrive. Also open to doing a more formalized club (which we should technically be doing with a club call sign) if people want to do that.
|
|
#
?
Jan 7, 2016 20:07
|
|
|
Picked up a fairly gently used Icom IC-775DSP today, 200W HF with internal antenna tuner and DSP, mains powered only (due to it using 28V for the PA) Previous owner sold it cheap because the DSP wasn't working (impossible to find new ones these days), turns out he sent the DSP card away to be modded to run eSSB (i.e. adding a relay to bypass the switched capacitor filters used in the AF chain). Sure enough, I installed the board and turned on the DSP function, no audio. Turns out whoever did the mod used far too thick wires for soldering directly to 0805 resistors and the connections broke in several places (underneath the potting stuff they applied), and two resistors cracked from the strain. After scraping all the silicone compound off and following the signal path and fixing up the bad joints and removing the relay bullshit the DSP works perfectly! New problem though (that I knew about), it occasionally basically stops receiving, dead S-meter, no SSB sound, I can get FM to work if I apply around 0 dBm of RF. LOs and output from the first converter is fine, looks like the issue is caused by the noise gate latching on for some reason (even when it's off), second IF signal is fine up to the gate diodes. Should be an interesting repair job, and after that I'll just have to align and fine tune the receiver BPFs (and maybe install a TCXO/OCXO) and it'll be ready for use!
|
|
#
?
Jan 10, 2016 00:13
|
|
|
Is eSSB really that useful? Sure it's better audio quality, but at the expense of a ridiculous amount of bandwidth. How much better does it really sound over something like AM? Isn't using digital voice with something like FreeDV far more practical? At least AM is standard on just about every rig, and anyone already set up for digital modes can do FreeDV, but eSSB requires special hardware.
|
|
#
?
Jan 10, 2016 03:49
|
|
|
longview posted:Picked up a fairly gently used Icom IC-775DSP today, 200W HF with internal antenna tuner and DSP, mains powered only (due to it using 28V for the PA) With the dead receiving, that sounds like the exact problem I had/have with an ICOM IC2200H. Audio cuts off like someone let go of the key, which I thought was happening. Eventually by having another receiver and heard the audio continuing was the only way I found out. I never could find out what exactly that's called (the issue) or a fix; if you ever do it'd be great if you or another person could share some insight!
|
|
#
?
Jan 10, 2016 04:51
|
|
|
xergm posted:Is eSSB really that useful? Sure it's better audio quality, but at the expense of a ridiculous amount of bandwidth. How much better does it really sound over something like AM? [rare 290 post] essb is garbage in practice and all those goobers should just go pick up old AM transmitters and actually sound good. *however* some of the concepts of essb, such as having a good mic -> preamp -> comp/gate -> eq feed into your radio's modulator input, are *great*. You don't have to push bandwidth to run nice eq and comp and have a punchy but smooth signal on ssb
|
|
#
?
Jan 10, 2016 06:14
|
|
|
So I'm actually going to get around to picking up at least my Technician's license this year. but the book I got (and barely used) is 2010-2014; is there a site somewhere that shows the delta between the 2010-2014 and the current pools? Or do I have to do a manual diff between the two to make sure I get all the changes? Figure it'll save me $20.
|
|
#
?
Jan 10, 2016 08:27
|
|
|
Jonny 290 posted:[rare 290 post] essb is garbage in practice and all those goobers should just go pick up old AM transmitters and actually sound good. Hell, I do that stuff even for VOIP like teamspeak/skype. You don't need ultra spendy studio equipment: even the junk products out there handle voice communications fairly well. It's not like the guy on the receiving side of an HF signal is going to hear the differences between a $1000 compressor and a $100 one! I've been meaning to give this freeware windows based DSP a try. It's a drat shame the program uses a graphic equalizer rather than a parametric, but, free. (Freeware Virtual Audio Cables may be useful) xergm posted:Isn't using digital voice with something like FreeDV far more practical? FreeDV has much, much different goals than eSSB. It's extremely low bitrate, for a digital voice codec, and sounds pretty awful. It makes that sacrifice to eliminate HF noises while only using 1.25kHz of bandwidth. https://www.youtube.com/watch?v=8YvFzNJiwMg The Mumble/Teamspeak servers I use have their quality set to between 35kbps-45kbps. FreeDV is 0.7-1.6kbps and consequently sounds rather robotic.
|
|
#
?
Jan 10, 2016 10:01
|
|
|
uapyro posted:With the dead receiving, that sounds like the exact problem I had/have with an ICOM IC2200H. Audio cuts off like someone let go of the key, which I thought was happening. Eventually by having another receiver and heard the audio continuing was the only way I found out. I never could find out what exactly that's called (the issue) or a fix; if you ever do it'd be great if you or another person could share some insight! I doubt the 2200H has a noise gate for this problem to appear in, since that's usually a HF radio feature (except for those fancy SSB VHFs), but a lot of things could be happening to cut the receive. First thing to check is often the LOs, if those go then nothing works anymore, then with HF and even VHF radios these days a decent scope can trace the RF through the receiver path as long as enough signal is there. Another place to start is in the demodulated AF chain, check if audio is present at the discriminator, if it is then the receiver part is working and it's a squelch/AF signal path issue. -- Just fired up my 775 again to much better conditions than yesterday so I can actually test the DSP on voice signals. It definitely helps with broad band noise and other crap, not as nice as the latest and greatest from the big three but not bad either. Also confirmed that the intermittent loss of signal is caused by the control signal for the noise blanker gate, so the whole blanker circuitry is something to take a closer look at.
|
|
#
?
Jan 10, 2016 10:17
|
|
|
movax posted:So I'm actually going to get around to picking up at least my Technician's license this year. but the book I got (and barely used) is 2010-2014; is there a site somewhere that shows the delta between the 2010-2014 and the current pools? Or do I have to do a manual diff between the two to make sure I get all the changes? Figure it'll save me $20. http://www.nc4fb.org/wordpress/question-pool-comparisonbrtechnican-2014-2018-v-technician-2010-2014/ Just some added it looks like; if you want to see all the current questions you can check out hamstudy.org, QRZ, or another of your friendly neighborhood apps.
|
|
#
?
Jan 10, 2016 18:25
|
|
|
Found this over in the OSHA thread. Be extra careful when messing around with the insides of a tube rig. Ponderous Saxon posted:The sorts of HV supplies you need to drive vacuum tubes scare the hell out of me. 7600V @20A went across this dude's hand (not too gory):
|
|
#
?
Jan 11, 2016 14:55
|
|
|
xergm posted:Found this over in the OSHA thread. Be extra careful when messing around with the insides of a tube rig. I knew there was a reason I never picked up those old tube radios at ham meets. -- IC-775 still working pretty well, DSP is quite good especially considering it's 20 years old. Decided to upgrade a couple of the power supply caps for fun, main power was made by Rubycon, despite being 20 years old there was no sign of bad caps. I suspect the noise blanker latchup was caused by misaligment in the noise amplifier circuitry, for now I've adjusted it down so it doesn't work at all. I'll have to borrow a pulse generator from work to generate the 1ms/100ms pulse train I need to tune the sensitivity properly. Another issue that I knew about but hadn't seen before, earlier it stopped generating AF in USB, then LSB, then both. AM and FM worked and the S-meter was showing signal, so it's not the noise blanker acting up. Turning the DSP on/off did nothing so that's not the issue. Not sure what's up there, best guess is that one of the LOs or BFOs didn't properly change over (most of those are generated by DDS chips with a serial interface to the main CPU), either that or a pin diode switch setting error. A working S-meter almost certainly puts the issue in the third or fourth converter anyway.
|
|
#
?
Jan 11, 2016 21:40
|
|
|
xergm posted:Found this over in the OSHA thread. Be extra careful when messing around with the insides of a tube rig.
|
|
#
?
Jan 11, 2016 21:44
|
|
|
Honestly lacking a noise blanker is not that big of a deal for HF/SSB, as long as you have some level of filtering available, and maybe iF shift. Sounds like that radio has really fallen apart, good on you for having the patience to deal with it.
|
|
#
?
Jan 14, 2016 13:44
|
|
|
I'll get the noise blanker working again as soon as I remember to bring the pulse generator home, strangely I have nothing on hand that can generate a 1% duty cycle pulse  Had a look at the high level schematics and the SSB audio dropout with working S-meter looks to be an issue caused by either the fourth converter or the fourth LO. It could also be the audio switchers but I suspect not since those are cycled when I switch the DSP on/off and when switching to AM. AM and AGC voltages are tapped off at the third LO and both of those were still working. 4th LO is generated by an Icom DDS chip, but I mainly suspect it's a signal integrity issue or a problem with the power supply decoupling since rebooting the radio fixed it. There's four identical DDS sub-boards for the various frequencies, all of which are on a common one-way SPI-like bus (I think the DDS ASICs just have a serial input shift register + some address decoding internally). If it happens again I'll leave the power on and check if a) the tuning in AM still works and b) pop off the panels and check the 4th LO output, that should tell me enough about the problem to know where to look. In any case I decided to dismantle the AC power supply to see if it had any bad caps, ESR checked out, but I replaced the 14V output caps with some ultra-low ESR types I had on hand to avoid any future problems.  It's definitely the easiest HF radio to work on I've seen, the three boards on the bottom basically make up all of the receiver and exciter, on the top side there's a switch mode power supply, the PA module and the auto tuner/low pass filter board. The modules on the top all have easy to access connectors and a couple of screws to hold them in place. All those flex cables go to the front panel, which contains the main CPU and a sub-CPU that handles the display + some 14V distribution. Almost all the control signals for pin diodes, relay switching etc. go over serial I/O expanders, which reduces the amount of wiring by a huge amount.
|
|
#
?
Jan 14, 2016 19:09
|
|
|
Well I was going to take the General exam today but the local group moved it to next week and didn't update their online calendar. 
|
|
#
?
Jan 17, 2016 02:33
|
|
|
C.M. Kruger posted:Well I was going to take the General exam today but the local group moved it to next week and didn't update their online calendar. That reminds me of something i've seen. I was checking out the ARRL schedule, and one place was offering what looked like bi-weekly exams offered at a Jacks restaurant. One like the one on this page: http://www.eatatjacks.com/locations/ I was surprised they offer the exam inside of a restaurant since they aren't always quiet inside.
|
|
#
?
Jan 18, 2016 01:49
|
|
|
That's kinda strange. Maybe the local club has their meetings there and they've got enough VEs showing up that they can do tests as well? Anyways, I passed the general exam today. I've also gotten in contact with somebody selling their IC-718 locally for a good price. Suggestions for a power supply and tuner and anything else I'm forgetting? Right now I'm looking at this power supply but I'm not quite sure about tuners, would this be what I want? I mean I figure that people used manual tuners just fine for ages, so I can skip starting out with a fancy autotuner. For a antenna I'm kinda limited in space so I suppose some kind of end fed matchbox with 30-40 feet of wire and a PVC pole on the other end would be my best option?
|
|
#
?
Jan 23, 2016 21:27
|
|
|
Do you really want to run a radio that can draw 20 watts full tilt on a sketchy looking switch mode supply (with little information available on line and even fewer reviews) that claims a max output of 23 watts? The tuner looks fine. Bog standard, should do the job if they assembled it correctly/after you fix it.
|
|
#
?
Jan 23, 2016 21:53
|
|
|
I don't know, that's why I'm asking.  So something like these instead then? I picked the other one because it was the one Universal listed down in the accessories section for their page on the IC-718. http://www.universal-radio.com/CAtalog/hamps/3440.html http://www.universal-radio.com/CAtalog/hamps/5837.html
|
|
#
?
Jan 23, 2016 22:46
|
|
|
Random wire antennas can work fine. Radiation pattern will be a bit random too, but it will probably work fine. Most people use a 1:9 unun to feed them, you want a good ground connection near the feed point, and avoid wire lengths that are near 1/2 wavelength of any ham band or it can be very difficult to tune. I'd recommend an auto tuner right away though, non-resonant antennas can take some work to tune and changing bands will require re-tuning every time. Most people I know seem happy with LDG auto tuners and a coax feed. For best performance you'll want to get something like an Icom AH-4 and place it near the antenna (coax losses essentially multiply with non-resonant antennas so reducing the tuner-antenna length can lead to significant improvements).
|
|
#
?
Jan 24, 2016 11:37
|
|
|
C.M. Kruger posted:I don't know, that's why I'm asking. Let's talk about switchers compared to linear/solid state power supplies first: why are you looking at switchers? Is it just cost? If so, quality ones cost nearly as much as quality solid state power supplies. Brand doesn't matter much, providing it's a known big boy - the guts are going to be largely similar. That can't be said for what you're looking at. If a good one was way more money I'd say if you just need something to get started with go for it, but a good one isn't that much more. Here's an Alinco switcher that's 25W continuous for $149: http://www.aesham.com/switching/alinco-dm-330fxt/ And an Astron 20 amp continuous for $139 (in your case the alinco is likely the better choice): http://www.aesham.com/switching/astron-ss-25m/ Be aware there are certain supplies/soft failure modes/configurations/positioning where a switch mode supply will introduce noise into radio. The better ones are better filtered, but it's still a thing people bitch about (especially QRPers or trying to drag signals out of the dirt) when it comes to switch mode supplies. Or you can get the tried and true Astron RS-35M (solid state linear) and you'll have nothing to worry about other than getting a hernia when moving it. Even if it breaks it's a reference design supply that a monkey can repair/upgrade. $200: http://www.aesham.com/transformer/astron-rs-35m/ The variable voltage model is $10 more: http://www.aesham.com/transformer/astron-vs-35m/ I've had an VS-50M for somewhere over a decade at this point and the only time it's given me trouble is when I left it in my garage and it got leaked on and powered up before I realized that. Some time to dry out and $3 in parts later I was back on the air.
|
|
#
?
Jan 24, 2016 22:07
|
|
|
|
| # ? Jun 5, 2024 01:22 |
|
|
Both the astron and pyramid ones with poo poo themselves if run near their max for any length of time. The Alinco kicks rear end, as will a modified server supply.
|
|
#
?
Jan 26, 2016 03:02
|
|