HFU HF Underground
Technical Topics => The RF Workbench => Topic started by: fieldstrength1947 on September 20, 2018, 1907 UTC
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Hello everyone, I'm new here on the board but definitely not new to radio experimentation, broadcasting, and electronics work.
I have plenty of experience on AM and FM with legal power levels, i.e. Part 15 and squeezing as much range as possible out of such systems. Recently though I've gotten interested in SW broadcasting. After doing a lot of research I've decided as a first project to try to build an AM modulated Michigan Mighty Mite, as described here: https://makerf.com/posts/so_you_want_to_be_a_shortwave_pirate
Half a watt ought to be plenty for me to mess around with for now. I don't want to go overboard. Don't have the resources to deal with the possible repercussions of yet higher power levels... ;)
Plus on SW it's much easier to make an efficient antenna on a small scale. Quarter wave at 7000 kc is 34.5 feet... not out of reach for hanging on a tree or something, just for giggles. Much better than Part 15 AM where your antenna efficiency is probably 5% or less even with the very best systems. Even 1/8 wave would probably be pretty good, right?
So I ordered up some parts from Mouser. As many crystals for different frequencies within the usual pirate bands I could find that they had in stock, plus any parts I didn't already have to make the circuit.
My question here is, anyone have suggestions for building this circuit and for SW broadcasts in general? I'm not looking for "MMM sucks, build {some other xmtr}". Any other projects can come later. Right now I'm just doing this because it's small and easy and all I have the resources and time for.
One of my specific questions I'm wondering about is whether I can put a potentiometer somewhere in the MMM circuit to vary the power output level. Ideally I'd have a mark somewhere on that dial for "legal" power with a certain antenna setup, so I could use it for micro-power broadcasts when I just want to send something to a radio in the house for fun. Unfortunately I don't have a field strength meter so it would be difficult to determine the actual legality, but I guess I could approximate by just walking around with radio.
Thanks!
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Seriously dude? Half a watt? Nobody is gonna hear you!
Edit
That was rude of me. You could use a variable power supply and run it at less than 12 volts. You could make a Variable RF attenuator from a potentiometer and a resistor.
There is a name for the circuit but I can't remember or find it now. I would look at the Chinese Pixie kit on ebay. For about $4 you get a nice PCB and a bunch of parts and there is alot of info on youtube.
https://youtu.be/pgTv9E5uTyI
https://youtu.be/Hct3WHUcnuA
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Those riceburners don't support audio input just cw right? Let's not take a steaming load on this. Didn't channel z do the experiment like 25watts/10 watts/1 watt during a broadcast and there was a slight decrement each time? The lowest power was still listenable. I bet he had a nice high dipole. Remember this broadcasting power thing is logarithmic. Lots more power needed to increase coverage. I bet half a watt with a nice inverted v at the highest height you can reasonably get would perform as well as a ten watt run into a vertical or shitty nonoptimized dipole. I say go for it and post when you will try broadcasting on the broadcast thread. If you can do breadboard shit go for it but I take the easy way out and would try copper board manhattan style coz that's the way I think and might work better. Just my 2 cents. Go ahead and yall rec.pets.cats flamewar on me. I encourage you to build that sob and learn from it.
PS yeah I miss alt.tasteless back in the day.
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I looked again for that variable attenuator circuit but can't find it. It is just a 200 ohm pot and a 51 ohm resistor. The input is the wiper of the pot. The resistor goes from one end of the pot to ground. The other end of the pot is output. More at Wikipedia:
https://en.wikipedia.org/wiki/Attenuator_(electronics)
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I bet half a watt with a nice inverted v at the highest height you can reasonably get would perform as well as a ten watt run into a vertical or shitty nonoptimized dipole.
It's a question of management of expectations. If you aren't expecting VOA-levels of coverage then you may find it satisfactory. ;)
I think that The Relay Station runs 1/2 W into a "good" antenna during the daytime occasionally and people actually do hear it.
If you can do breadboard shit go for it but I take the easy way out and would try copper board manhattan style coz that's the way I think and might work better.
I prefer dead-bug style - shortest connections between components in some cases.
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I think that The Relay Station runs 1/2 W into a "good" antenna during the daytime occasionally and people actually do hear it.
Indeed. I think sometimes even with less power ;D
One S unit is a power ratio of 4. Signals can be heard at even very low transmitter power levels.
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I think that The Relay Station runs 1/2 W into a "good" antenna during the daytime occasionally and people actually do hear it.
Indeed. I think sometimes even with less power ;D
One S unit is a power ratio of 4. Signals can be heard at even very low transmitter power levels.
you should know Chris because you hear damn near everything.
including a MMM doing a half watt at least a few times. i know that for a fact.
i also know that you and most everyone else has been hearing higher power MMM's for years.
i think the MMM is just fine. making more power out isn't that hard either.
with or without a added rf section filter the output or you'll be throwing harmonics everywhere.
the output level of the MMM is affected by how well you tune the variable capacitor if you build it with one instead of a fixed value.
i could add add a bit more but if you build it you'll learn. it's part of the FUN.
so try it you'll more than likely like it . you can always build something else later.
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If you Solder I can send you a PCB at min cost, or I can built it for you.
Have 3W, 10W, 40W & 150W designs.
I'm not a fan of dead bug construction as PCBs are so cheap!
Str.
p.s. why bother with 0W5? pointless unless you're TXing CW or you want no-one to hear you!. 10W is fine. No you cant adj pwr with a pot, again pointless, just operate from less volts. Nothing Legal about any power level on the freqs you suggest either!
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Those riceburners don't support audio input just cw right? Let's not take a steaming load on this. Didn't channel z do the experiment like 25watts/10 watts/1 watt during a broadcast and there was a slight decrement each time? The lowest power was still listenable. I bet he had a nice high dipole. Remember this broadcasting power thing is logarithmic. Lots more power needed to increase coverage. I bet half a watt with a nice inverted v at the highest height you can reasonably get would perform as well as a ten watt run into a vertical or shitty nonoptimized dipole. I say go for it and post when you will try broadcasting on the broadcast thread. If you can do breadboard shit go for it but I take the easy way out and would try copper board manhattan style coz that's the way I think and might work better. Just my 2 cents. Go ahead and yall rec.pets.cats flamewar on me. I encourage you to build that sob and learn from it.
PS yeah I miss alt.tasteless back in the day.
Agreed, a dipole is an excellent antenna, almost impossible to improve or beat their efficiency with something as simple. A horizontal dipole within 400 miles of a certain smolinksi would ensure plenty of nvis signal coverage, if you want folks to copy further away, see if you can rig up a vertical dipole.
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I think that The Relay Station runs 1/2 W into a "good" antenna during the daytime occasionally and people actually do hear it.
Indeed. I think sometimes even with less power ;D
One S unit is a power ratio of 4. Signals can be heard at even very low transmitter power levels.
you should know Chris because you hear damn near everything.
including a MMM doing a half watt at least a few times. i know that for a fact.
i also know that you and most everyone else has been hearing higher power MMM's for years.
I believe I've heard Relay Station when he's running 100 mW or so. If you do the math, it's not too surprising, assuming you have decent conditions. Since you only lose an S unit per factor of 4 power reduction, you can go from 10 watts carrier to 625 mW, just over half a watt, and only lose 2 S units. 150 mW is only another S unit below that. You need very low noise levels to hear anything, though. Both atmospheric and local. The 22 meter beacons typically run 4 mW, as another example of low power. Of course this is CW not AM.
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The whole reason for using shortwave is to use skywave propagation and to broadcast rock music mostly from the late 60's to early 70's.
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The whole reason for using shortwave is to use skywave propagation and to broadcast rock music mostly from the late 60's to early 70's.
Says who? ::)
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Thanks for all the help and advice, everyone!
Last night and this morning I built the transmitter. It looks quite nice in its little weatherproof exterior box. I put terminals on the outside of it for the crystal so it's easy to change frequencies.
And it works, first try too; I didn't have to change anything. The signal is clean and clear, with only a little hum. Handles reasonably loud audio levels nicely.
I hooked it up to 18 feet of 18 gauge bare copper wire (about 1/8 wave) as a test antenna, to see what it does in the daytime. Goes about a mile... not too bad, I guess. The same as my Part 15 AM setup, though. I just have the wire hanging from a tree straight up and down. (the initial tests were done with a 3 foot whip antenna and the range was about a block.) Putting a second 18 foot length on the ground terminal 90 degrees to the vertical changed nothing.
So I guess now I need advice for antennas... what would y'all recommend for antennas? I've heard a lot about the inverted V type. If I were to build one, what ought I to build it out of? Does it need to be something very thick, like copper tubing, or could it just be thick gauge wire?
I'm a little in the dark as to shortwave antenna design. Also, how crucial is grounding? I can ground it well if I need to but will it make a difference range-wise?
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cool you got it going .
there will be some who disagree with this.
i used a dipole as a inverted v just high enough to keep the ends off the ground about a foot .
and no earth ground .
1/2 watt carrier approx. was heard last night by ChrisSmolinski and it wasn't in his backyard by a long shot.
no location will be provided so don't ask.
https://www.hfunderground.com/board/index.php/topic,46168.0.html
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Antenna choice usually boils down to several factors; your intended audience and their location, your location, and your available real estate. If you want to reach most of the DX'ers in this country, your aiming for the east coast. If your close enough to the east coast to hit it with a dipole or inverted V via NVIS, then that's all you'll need. If your closer to the mid section or west of the country and want to hit the same people, a vertical would be a better choice as it focuses more radiated power toward the horizon.
The down side to hitting the coast from the coast is that your limited to the hours when NVIS is effective, usually during daylight hours to just after sunset. This will be influenced by solar activity, and there will be times even during the day that NVIS is not possible on 43 meters, like when the MUF is low. Likewise, skywave (on 43 meters anyway) is best during dark hours.
+-RH
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Dipole, approx 68' at 20' above ground.
This will give NVIS (Look this up!)
Daytime ONLY.
Nighttime will need way more power and a vertical.
Str.
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cool you got it going .
there will be some who disagree with this.
i used a dipole as a inverted v just high enough to keep the ends off the ground about a foot .
and no earth ground .
1/2 watt carrier approx. was heard last night by ChrisSmolinski and it wasn't in his backyard by a long shot.
no location will be provided so don't ask.
https://www.hfunderground.com/board/index.php/topic,46168.0.html
Thanks for the info on the power level, I enjoy the technical challenge of picking up lower power transmissions. Your signal was getting out great for half a watt. There were a few occasional peaks to SIO 333. If you happen to have an eQSL for a 1/2 watt transmission... I have a recording. And thank you for the ID ;D
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Welcome to the dark side. All you need is a coax-fed, half-wave horizontal dipole cut for your operating frequency. Mount it as high as you can. No tuner required, and about as simple as you can get for good performance. That's all I've ever used, and my results speak for themselves: 380 mW beacon received in France, 1.1 watt Corsette received 1,000 miles away, 16 watt LuLu received in Japan, 25 watt Commando regularly heard in New Zealand.
Chris Smolinkski and I did some low power experiments, and you can hear for yourself the difference between 1.1, 14, and 25 watts: https://www.radiohobbyist.org/blog/?p=271 (https://www.radiohobbyist.org/blog/?p=271)
Also, if you want to try other proven transmitter designs, or need help with a build, please join the homebrewpirateradio Yahoo Group: https://groups.yahoo.com/group/homebrewpirateradio (https://groups.yahoo.com/group/homebrewpirateradio)
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"Says who? ::)"
Says someone who can't find it on FM anymore! The best that's out there is 15 min. of tunes you heard thousands and thousands of times then 15 min. of commercials.
But now we have bittorrent and youtube-dl so we can rebuild our long lost vinyl collections.
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The whole reason for using shortwave is to use skywave propagation and to broadcast rock music mostly from the late 60's to early 70's.
Says who? ::)
Only a philistine wouldn't consider this the heights of musical development;
https://www.youtube.com/watch?v=M0k0z2MtvLY
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But now we have bittorrent and youtube-dl so we can rebuild our long lost vinyl collections.
Lost vinyl is not on the Internet. Gots to go to the record store.
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I should have said "music collection of ...". Do you mean one of these?
https://en.wikipedia.org/wiki/Record_shop
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I should have said "music collection of ...". Do you mean one of these?
https://en.wikipedia.org/wiki/Record_shop
Thar ye go. 'Tis exactly that.
If you want to make a backup of your vinyl, then record it to tape (something 1/4" or wider... the cassette tape will do in a pinch, but has something to be desired).
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Thanks for the suggestions everyone -
Will reply in detail later but suffice it to say I'm testing at the moment with a quick and dirty half wave dipole, since I have room for it and I don't have the resources to put up an inverted V yet. I'll figure that out at some point. But in the meantime, this dipole gets my signal a fair ways out, by which I mean about 2 miles. Ha, some optimization will be in order.
Of course I do wonder what it's doing skywave wise.
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2 miles is rather weird as you will NEVER get any 'Local' coverage so don't expect any!
Min skip distance is around 200-300 miles but will vary.
Hence the need for a bit of power as the signal has to go up a far way (30-150miles) to be diffracted by the ionosphere to come back down again.
Plenty of online SDR's to monitor your signal and good for comparing antennas too (you'll need to have both connected via a switch so you can flick between them)
Str.
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Thanks for the suggestions everyone -
Will reply in detail later but suffice it to say I'm testing at the moment with a quick and dirty half wave dipole, since I have room for it and I don't have the resources to put up an inverted V yet. I'll figure that out at some point. But in the meantime, this dipole gets my signal a fair ways out, by which I mean about 2 miles. Ha, some optimization will be in order.
Of course I do wonder what it's doing skywave wise.
what frequency and UTC times are you testing at so i can look out for you?
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All you need is a coax-fed, half-wave horizontal dipole cut for your operating frequency. Mount it as high as you can. No tuner required, and about as simple as you can get for good performance.
exactly this.
except that my horizontal dipole is full wave instead of half wave and its about 30-35 feet above the ground in the clear which is why i cant use 5150Khz, it was just too long and unstable.
after trying many different antenna/feedline designs and heights over the years, this works the best.
the downside is not being able to use other frequencies with 1.0 VSWR although VSWR isnt "everything".
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I must be missing something. Please describe your antenna and feedline for me.
This website:
https://www.tutorialspoint.com/antenna_theory/antenna_theory_full_wave_dipole.htm
Says this:
Disadvantages
The following are the disadvantages of full-wave dipole antenna.
Heat dissipation
Wastage of power
No radiation pattern
No directivity and no gain
Due to these drawbacks, the full-wave dipole is seldom used.
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I must be missing something. Please describe your antenna and feedline for me.
This website:
https://www.tutorialspoint.com/antenna_theory/antenna_theory_full_wave_dipole.htm
Says this:
Disadvantages
The following are the disadvantages of full-wave dipole antenna.
Heat dissipation
Wastage of power
No radiation pattern
No directivity and no gain
Due to these drawbacks, the full-wave dipole is seldom used.
it appears from the drawing diagram, that they are including open wire feedline as part of the antenna.
i have coax fed right to the top of the dipole.
it did not operate as expected using full-wave with open wire feedline but worked perfectly with coax.
since im using a single frequency, coax will work in my situation.
i would tend to believe using highly shielded coax as feedline to the dipole is akin to bringing the TX right at the center fed part of the dipole.
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Testing in a bit here on 6780 kc starting at about 0000 UTC.
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If you feed a 1wl antenna at the end with coax, you may need an xformer as the coax is typically low z and the feed point of the 1wl antenna is about 2k ohms or even higher.
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Carrier on at 0005 UTC, audio fully on at 0010. Would appreciate any contacts.
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For reference, I'm starting to think that my crystal is not exactly on frequency, either that or my antenna isn't tuned, or something. Changing the position of the variable cap changes the frequency a little, so I can get it spot on, but then my audio goes away and the carrier goes weak.
It seems to be on 6782 kc.
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I'm seeing signals at 6779.5, 6781.3 and 6781.7...... too weak for any modulation
rgg
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Could be either one of those last two. Just boosted the volume a little just up to the point of distortion.
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Off at 0036?
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Nope... maybe wait about 30 minutes or an hour, might get better skywave propagation then.
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I can see my carrier on a WebSDR 575 miles away! Woo!!
Confirmed by turning it off and on and watching the carrier disappear and appear again. Now I feel like I've accomplished something. Couldn't hear any modulation though. Plus now it's faded out... oh well.
Was able to confirm by this that it is on 6781.7 kc.
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6780 is in one of the ISM bands, same (or similar) as 13560.
https://en.wikipedia.org/wiki/ISM_band
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"i would tend to believe using highly shielded coax as feedline to the dipole is akin to bringing the TX right at the center fed part of the dipole."
I've seen things that should work not work and things that should not work work before.
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You'll need more power, simples....
Antenna wise a full wave dipole isn't 50R at the centre, stick to half wave or odd multiples of, 3 half wavelengths give 50R and a clover leaf pattern BTW.
Str.
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Off at 0838 UTC.
Perhaps one more short test during the daytime tomorrow.
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Testing in a bit here on 6780 kc starting at about 0000 UTC.
My overnight SDR recordings are 6800-7000 kHz, so I missed your test transmission.
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"i would tend to believe using highly shielded coax as feedline to the dipole is akin to bringing the TX right at the center fed part of the dipole."
I've seen things that should work not work and things that should not work work before.
as strange and as illogical as it may sound and be, my current antenna setup works very well and better than expected after a few years of trying different antenna and feedline configurations.
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Yeah don't believe quite all of the book values and antenna voodoo you read. An inverted v 20 feet up in the center and legs just off the ground to 6 feet up is only supposed to give NVIS. Why then have I seen 10 watts cover well over 1000 miles? Magic resonance I guess. My first 2-3 watt crap build was heard (poorly) almost the entire N-S distance of the US in the daytime, tossed center wire 20-25 feet high over a limb, edges maybe even touching the ground.
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i would tend to believe using highly shielded coax as feedline to the dipole is akin to bringing the TX right at the center fed part of the dipole.
What the TX sees looking into its end of the coax is based upon four things: 1) the coax's characteristic impedance, 2) the loss of the coax, 3) the length (in wavelengths) of the coax 4) the load at the other end of the coax.
You want the TX to see the antenna's inherent impedance? Make the coax length a whole multiple of a half wavelength.
Shielding doesn't have anything to do with it unless it's part of the active part of the coax and affects the characteristic impedance. (There are double-shielded coaxes for low-leakage applications, as an example of coax with shielding that does not affect characteristic impedance.)
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Even with a 50 foot antenna in sloper configuration (lowest point around 5 feet above ground level, highest point maybe 12 feet) NVIS and further distance propagation are both possible at modest power levels. Propagation conditions (read: luck and timing) also play big parts, so keep on experimenting - you'd be surprised what you can do with low power when the conditions are good.
I would recommend using a frequency closer to 6925 kHz if possible. The 6800-7000 kHz range is where many people with SDRs recording the entire band look at for activity. 6850-6975 is an even better range to shoot for (if possible). I know your rig is crystal controlled so if you have crystals for those frequencies they might get you better results in terms of listenership and reports. 6925 kHz is the "home channel" for 43 meters, followed by 6955 kHz. Just avoid using 6910 kHz and 6915 kHz as these frequencies are used by the U.S. Government for disaster relief operations and other emergency communications.
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Just avoid using 6910 kHz and 6915 kHz as these frequencies are used by the U.S. Government for disaster relief operations and other emergency communications.
and 6855Khz, this is used by the US Military.
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^Well said. 6940 kHz and 6945 kHz are often used for Link-11 data transmission by the US military as well. Check the HFU loggings for Shortwave Pirate [here: https://www.hfunderground.com/board/index.php/board,3.0.html (https://www.hfunderground.com/board/index.php/board,3.0.html)] to see if any other stations are on the frequency you plan to use before transmitting to avoid interfering with another pirate station. It's also a good idea to check the RocketChat chat room for HFUnderground to ask listeners if there are other stations on the air or utility users on a frequency you might pick. With low power, its extremely important that you use a clear frequency.
Which frequencies do you have available to you?
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Thanks for the good info on frequencies, guys!
What I did when I ordered the parts from Mouser is I just ordered as many crystals as fit the following criteria:
1. Not within an amateur radio band
2. Not being used by any current shortwave station that reaches North America
But obviously I need to update my criteria...
I don't have anything between 6800 and 7000. And looking back at Mouser it seems they simply don't stock any of those, at least not at the moment.
Anyone know where I could get crystals in that range?
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Yeah don't believe quite all of the book values and antenna voodoo you read. An inverted v 20 feet up in the center and legs just off the ground to 6 feet up is only supposed to give NVIS. Why then have I seen 10 watts cover well over 1000 miles? Magic resonance I guess. My first 2-3 watt crap build was heard (poorly) almost the entire N-S distance of the US in the daytime, tossed center wire 20-25 feet high over a limb, edges maybe even touching the ground.
To get tactical nvis coverage the antenna must be low to the ground, as in only a foot or two. Even then, it also depends on the ionosphere, muf, luf, etc.
https://brushbeater.files.wordpress.com/2017/04/1996-fiedler-near-vertical-incidence-skywave-communication-book-worldradio-books-2.pdf
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eBay is my first bet -
https://www.ebay.com/itm/FT-243-Radio-Crystal-Oscillator-6-9250-MC-Ch-320-M-P-Co-093-Pins/273025354397?hash=item3f91944a9d:g:VvQAAOSw8RZaW7KU:sc:USPSFirstClass!23235!US!-1 (https://www.ebay.com/itm/FT-243-Radio-Crystal-Oscillator-6-9250-MC-Ch-320-M-P-Co-093-Pins/273025354397?hash=item3f91944a9d:g:VvQAAOSw8RZaW7KU:sc:USPSFirstClass!23235!US!-1) - 6925 kHz FT-243 style
https://www.ebay.com/itm/FT-243-Radio-Crystal-Oscillator-6900-KC-Ch-319-Daughetee-093-Pins/253412122175?hash=item3b008a1e3f:g:USQAAOSwZoZaeO7z:sc:USPSFirstClass!23235!US!-1 (https://www.ebay.com/itm/FT-243-Radio-Crystal-Oscillator-6900-KC-Ch-319-Daughetee-093-Pins/253412122175?hash=item3b008a1e3f:g:USQAAOSwZoZaeO7z:sc:USPSFirstClass!23235!US!-1) - 6900 kHz FT-243 style
https://www.ebay.com/itm/FT-243-Radio-Crystal-6850-KC-Channel-317-Daughetee-Tested-Good/253374341295?hash=item3afe49a0af:g:RBEAAOSwFLBaXrLA:sc:USPSFirstClass!23235!US!-1 (https://www.ebay.com/itm/FT-243-Radio-Crystal-6850-KC-Channel-317-Daughetee-Tested-Good/253374341295?hash=item3afe49a0af:g:RBEAAOSwFLBaXrLA:sc:USPSFirstClass!23235!US!-1) - 6850 kHz FT-243 style
https://www.ebay.com/itm/6800-KHz-FT-243-Crystal/183403927542?hash=item2ab3b9d7f6:g:uPkAAOSwheZaoF95 (https://www.ebay.com/itm/6800-KHz-FT-243-Crystal/183403927542?hash=item2ab3b9d7f6:g:uPkAAOSwheZaoF95) - 6800 kHz FT-243 style
There are hundreds and hundreds of the FT-243 style crystals on eBay. Of course, if your rig uses a small crystal holder then you'll have to either source different size crystals or make an adapter.
I'll let other posters chime in when it comes to other sources...
If 6780 kHz is the closest you can get to 6800-7000 kHz then I would go with using that while you look for crystals that are a bit higher in frequency.
The criteria you list are pretty...open! Be careful that you're not transmitting in aeronautical bands or other frequencies used by safety of life communications. 6525 kHz to 6765 kHz is the closest HF aircraft band to 6-7 MHz. Your best bet is to stick to the 6765 kHz to 7000 kHz range (which is allocated as a fixed/mobile band). 6200 kHz to 6525 kHz is the 6 MHz HF-SSB marine mobile band and while it is popular with European pirates and a stray SW broadcaster, there are safety of life communications in that band that you certainly don't want to interfere with either. The 49 meter broadcast band is 5900 kHz to 6200 kHz and is also popular with European pirates.
For the time being, it may make the most sense to stick with 6780 kHz thereabouts (don't use 6770 kHz, as that is used by Old Time Radio, a low power pirate station that is on the air basically 24/7) or pick an empty frequency in 49 meters if you have crystals for that.
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In this thread:
https://www.hfunderground.com/board/index.php/topic,45682.0.html
I posted this:
https://www.ebay.com/itm/6250KHZ-CHANNEL-293-FT-243-CRYSTAL/191993567215?hash=item2cb3b557ef:g:6eQAAOSwPCVX~itB
I just checked and they have 3 available.
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If your transmitter will accept TTL/CMOS drive at 5V, you can use these oscillators programmed by digikey to any frequency between 1-133 MHz. The cost is nice too.
https://www.digikey.com/product-detail/en/cardinal-components-inc/CPPT1-HT0PT/CPPT1-HT0PT-ND/387755 (https://www.digikey.com/product-detail/en/cardinal-components-inc/CPPT1-HT0PT/CPPT1-HT0PT-ND/387755)
+-RH
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Thanks! I went ahead and got the 6850 kc crystal; hopefully that's a good channel... in the meantime I'll keep using 6780 if I do any more test between now and then.
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If you're going to go with crystal control, I'd get the 6900 kHz and 6925 kHz crystals as well. They're cheap and having the ability to move around the band as needed is nice.
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Testing again tonight on 6780, in celebration of the new Logic album - playing YSIV on repeat.
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I prefer bad words from a girl with a guitar.
https://www.youtube.com/watch?v=dv3QWOueK74
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I prefer bad words from a girl with a guitar.
https://www.youtube.com/watch?v=dv3QWOueK74
Hahaha... to each his own. Somehow to me it seems more appropriate in a hip-hop context. Also the legacy of pirate radio broadcasting hip-hop music, but I guess that's also kind of diluted by the mainstreaminess of hip-hop now.
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https://www.youtube.com/watch?v=vS-zEH8YmiM
"the legacy of pirate radio broadcasting hip-hop music"
Hip-hop is legacy? Look it up on wikipedia, then look up rock and roll.
https://www.youtube.com/watch?v=5DGF1tQ8V4o
https://www.youtube.com/watch?v=dAmSILueixA
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Any luck with the 6850 kHz crystal and/or purchasing the 6900 kHz and 6925 kHz crystals?