I know, you're going to ask, "why would you buy a 20m SSB kit?" The short answer is: 14300; the maritime nets. See, I plan on doing some sailing, hopefully, nothing is certain, but... I have an Icom IC-M700 marine radio, which works just fine on 20m. Actually, it works everywhere except on CB frequencies. Problem is, it gobbles 2A on receive! I am used to 35mA from my MTR... I need something I can leave plugged-in for long periods without depleting the boat's battery, which already has to power the VHF 24/7 and navigation lights at night. I came up with two choices:
- The MFJ-9420X
- The BitX20A from qrpkits.com
In the end the BitX20A won, but i am still not sure that was the right choice. I really, really like the MFJ-9420. I also really like building kits, humm... I really like to save $60. I know, not much of a difference, but I'm broke right now, so every little bit saved does help.
I hope the Hendricks, actually, Pacific Antenna kit, after change of ownership, is easier to put together than the Indian kit. I did buy an Indian kit a couple years ago but gave up; and that's from someone who built a K2... I only remember the instructions being dismal, or rather non existent. Maybe it is better now, who knows, but I wasn't going to take the risk. From what I've read, the Hendricks directions aren't that great either, though they always had good instructions for their other kits. I've bought a handful from qrpkits.com and never had any trouble.
The BitX20 seems like a good design and gets pretty good reviews. Output is 10W, like the MFJ-9420. It does not have an S-meter however, and no provision for CW. Both can be added later, but some knowledge is required. It does have a digital readout, unlike the MFJ, but that's a moot point.
This new radio will be a great complement to my K1 and MTR, which remain my main radios. If it wasn't for sailing, I probably would have rather bought a KD1JV Survivor, also from qrpkits.com, for NVIS operations on 80. I still might buy one... Ray, how do you like yours? Actually, the Survivor and Weber Tri-Bander use the same case, imagine a nice little stack... Incidentally the BitX20A has the same width... You see where I'm going with this... :o
I will be posting photos and my account of the build in this thread. My order was placed this afternoon, let's see how fast the new qrpkits.com can deliver...
Gil.
You're headed down the path I'm on. What I should have is an MTR for when weight counts and an FT-817 for when weight isn't that important and I want a rig that will do everything. Used 817's can be had for under $550. Between my KX1, MFT-9420, and TenTec R4020 I have over $600 into those rigs. Still, building and having lots of little rigs is just so much fun.
Don't kill the messenger here, but CW QRP is not a "Prepper" radio.
The prepper radio needs to be able to do it all for anyone that can read an SOP, licensed or not.
Nothing fits like the 8x7 series radios.
I just bought an FT-817 that's software modify able for $450 with 3 batteries (if anyone want the batteries they are yours for shipping) and having 2-160 in one rig that size with packet, etc...
After 16 years there is still no better rig that does it all. Major market share being missed IMO.
- Jim
Hello Jim,
Clearly CW doesn't do it all. It is only one component of a radio prepping strategy. The FT-817nd certainly is a great radio. It does draw 450mA on receive though, and is pretty pricey. If you are in a group and need to send out a long range patrol, you're probably not going to send them out with an 817. A tiny 80 or 40m CW rig would work NVIS on eight AA cells for a week..
Portable radios appeared in WWII, and they were definitely QRP. You don't get more "prepper" than that. You just couldn't beat them for mobility. The same applies today. A party operating 100 miles away needs to use NVIS. They probably would have to carry a whole lot of equipment and food for a couple weeks. Adding even a slightly heavier radio would be a big hurdle. Morse code also does add a layer of privacy, especially reasonably fast code. Low power NVIS is also hard to direction-find...
So, I'd say that CW QRP is definitely a prepper radio, very much so. It is just limited in its application, though it does what it is supposed to do very well.
Gil.
Agreed on all, except having two code talkers in one group is probably as rare as hens teeth. :)
When I say prepper group I'm talking about family / neighborhood sized groups.
Your scenario and historical application of the QRP CW could find its place in a resistance movement, but those are militia groups not preppers IMO.
For a local group, 2M HTs is the backbone of comms but having he ability to reach a community 170miles away where my Mother-In-Law lives is a good reason for an HF.
We all see our scenarios the way we want to though, best to prepare for the worst and hope for the best.
For a group called "radio preppers" I seem to only see CW topics most of the time.
Not complaining because that's what I'm into learning on the comms end of prepparing but I did expect something different when I joined.
Doesn't help being the only guy in the room that doesn't speak the language, I just KNOW you all are talking about me! :)
- Jim
Jim
I like what you said.
Bob
Quote from: K7JLJ on May 26, 2015, 01:55:59 AM
Agreed on all, except having two code talkers in one group is probably as rare as hens teeth. :)
When I say prepper group I'm talking about family / neighborhood sized groups.
Your scenario and historical application of the QRP CW could find its place in a resistance movement, but those are militia groups not preppers IMO.
For a local group, 2M HTs is the backbone of comms but having he ability to reach a community 170miles away where my Mother-In-Law lives is a good reason for an HF.
We all see our scenarios the way we want to though, best to prepare for the worst and hope for the best.
For a group called "radio preppers" I seem to only see CW topics most of the time.
Not complaining because that's what I'm into learning on the comms end of prepparing but I did expect something different when I joined.
Doesn't help being the only guy in the room that doesn't speak the language, I just KNOW you all are talking about me! :)
- Jim
Members here drive the content so if your not seeing something feel free to start it up. No one will criticize you for a non CW thread. I'm not a CW guy (yet) so i like to see info about all the modes.
As with anything you got trade offs. You can have a 2m HT that can only go few miles or you can have a CW rig, antenna, batteries and a solar panel to charge for the same weight but a lot more comms features. Of course you also need the skill.
I'm trying to build a group that can work 2m and SSB and have some key CW operators that relay info but this takes time, skill and dedication to learn and understand a new piece of equipment.
I agree with everybody. I'm not sure that's technically possible but it's nice to be agreeable sometimes. All the radio modes have potential as prepper modes depending on your specific imagined scenario. In Gil's scenario an extremely portable cw radio is the ideal thing. In other's it might be digital, SSB or FM. I think the fact that CW gets talked about so much here simply is an indication of how much we enjoy that particular mode. In my opinion and in the opinion of many here it is simply more fun and rewarding than other modes and we all tend to talk about our preferred modes more than other modes. I see lots of potential benifits to using PSK31 for example but in the pursute of my radio hobby I don't enjoy it as much so it gets less used by me and thus less talked about.
QuoteFor a group called "radio preppers" I seem to only see CW topics most of the time.
Yes... I didn't plan it that way... All modes are welcome here of course and they all have something to offer. CW is so efficient, it is natural that it would be much talked about.
Of course 2m HTs are what I would get first for a group. I would also have an SSB HF radio and QRP CW rig. They all have different missions.
I am about to write a short post on NVIS, stay tuned...
Gil.
Quote from: vwflyer on May 26, 2015, 04:34:29 PM
...I think the fact that CW gets talked about so much here simply is an indication of how much we enjoy that particular mode. In my opinion and in the opinion of many here it is simply more fun and rewarding than other modes....
Agreed. Rewarding. And the richest ham, with a field of towers, can't buy Morse skills. It is something that has to be earned. There's not many ways a guy living in a trailer park can get a rich guy to be jealous of him. Morse skills is one.
WRT prepping, like so many things, the answer is "D all of the above". If we knew what we were prepping for we could say what "the best" is. We don't, so we cover our bases.
Quote from: cockpitbob on May 26, 2015, 05:12:06 PM
.............. If we knew what we were prepping for we could say what "the best" is. We don't, so we cover our bases.
Speak for yourself, personally I know what I'm prepping for - an earth invasion of highly trained, advanced extra terrestrials.............basically space ninjas.
Quote from: KK0G on May 27, 2015, 08:43:40 AM
Quote from: cockpitbob on May 26, 2015, 05:12:06 PM
.............. If we knew what we were prepping for we could say what "the best" is. We don't, so we cover our bases.
Speak for yourself, personally I know what I'm prepping for - an earth invasion of highly trained, advanced extra terrestrials.............basically space ninjas.
Ahhh geeezze... you've been talking to RadioRay again.
Wally
Quote from: Quietguy on May 27, 2015, 05:55:02 PM
Quote from: KK0G on May 27, 2015, 08:43:40 AM
Quote from: cockpitbob on May 26, 2015, 05:12:06 PM
.............. If we knew what we were prepping for we could say what "the best" is. We don't, so we cover our bases.
Speak for yourself, personally I know what I'm prepping for - an earth invasion of highly trained, advanced extra terrestrials.............basically space ninjas.
Ahhh geeezze... you've been talking to RadioRay again.
Wally
Oh sure, go ahead and laugh it up while you can. Have ever seen what space ninjas can do?! Well I haven't either but I imagine they're scary as hell. If you think regular ninjas are scary just think what robot space ninjas are capable of. I read all about it on the internet. ;D
The kit should be here on Friday! I can't wait to start on it. I need to order a ten-turn potentiometer and a varactor for a wider tunnig range. That should be the only deviation I'll make from the kit.
Gil.
Gil, you're really in a building mood these days :) . Be sure to leave some time to get outdoors and throw a wire up in a tree. I will be just as soon and the spring crop of mosquitoes dies off.
You're right Bob, I plan on doing just that :-)
The BitX20A is to take sailing, and hopefully I'll get to go in a couple months!
Gil.
Well, I finished the BitX20. It doesn't work :(
I've built so many kits, including a K2, and they all worked immediately... This kit was no walk in the park. First, the manual is riddled with errors. To anyone wanting to build one, DO NOT follow the manual to the letter. Some resistors are labeled with the wrong colors, especially the 10 Ohm, 100 Ohm and 1 kOhm variety... Follow the component values, not the colors. Download the BitX17A manual, it is much better.
Then I inverted the two molded inductors, broke one while unsoldering it >:( I ordered a replacement, but now I have to wait. The VFO works mind you, I get about a 150kHz tuning range, though I might replace the polyvaricon with a varactor later for more range. The BFO seems to work too, I measured the 11mHz signal with a cheap frequency counter. I did hear some signals and voices but very faint. There is definitely a gain problem somewhere. The transmitter section does not seem to output anything, another mystery to solve. I hate troubleshooting.
Well, if I had a scope and an HF signal generator, it would be much simpler... Anyone has an old 20mHz oscilloscope pickup up dust in his basement?
It will be a week before I get back to it. I hate having $200 sitting like that...
Gil.
"space ninjas..."
Well, just remember that > I < am the one to whommmmm the aliens gave a silver rubber jump suit! I'd rather not explain what I had to do to earn it though ...
-...-
From experience and for my use, the go-to in wilderness or foreign remote assignments has been Morse because of very low power requirement for the same intelligence transfer which translated in tiny power consumption. The ability to easily and quickly send a written text/cipher text message with minimal support/consumption was important. 35 mA on receive for an MTR RIG and a 13 to 18 dB SYSTEM GAIN FOR CW compared to voice is why I use Morse 99% of the time, especially in the field where I carried my gear in addition to my normal load-out and had to recharge batteries in my "spare time" ;-/
In a grid-up or easy recharge environment , I might use digital like the winlink system, using RMSexpress on the tablet. However, it and especially
Voice requires a much better signal to noise radio than Morse for the same exchange. For me personally , I have little use for voice outside of quick reaction tactical comms and it's very tough to support in the field due to the required power levels .
It's FUN however to chat with people in voice if that is what you're into and a necessity when dierating a group quickly, usually in close area operations. We ALL agree "Radio is magic!
Hello Ray,
Well, voice is not what I'm into but I want to be able to listen to and participate in the 14300 maritime nets while on the boat.. So, now I have to troubleshoot this thing :( The only kit I built that didn't work right away uses USB! Go figure :o The Morse gods know I did something wrong and are punishing me!
Gil.
Oh yes - MMSN is great for sailors and life aboard is supported by HF Radio. How well I remember.
Ray
I am not a prepper, though I can show you how to pickle anything in about 5 days without vinegar or cooking, and I can take you out in a field and show which grass seeds to pick, grind them up and make pancakes. Just old world methods. I regret i did not learn CW long ago. One thing most forget about CW. Its not just Morse code. Letter swapping is easy light security, however you can make you own code for a neighborhood watch, where a combo of just 4 dots and !dashes can mean 16 different sentences. (binary 4 bit) eight would give you 256. Think of it. #14 (i am at wiggens) # 46 (i have food) #67 (I need water) # 108 (I am ok for now). NVIS is also harder to trace than say uhf or vhf. I am going CW all the way.
You can do the same with phone using mike breaks and have the ability to talk in a hurry if needed..
Two breaks means approaching from East. Then all hell breaks loose... "They broke through the roadblock and have grenades, 100M from base!"
Try tapping not that out under stress ;)
- Jim
Hello,
A code like this is fine as long as it is short. Remember, Morse code is only 26 letters... So, if your code is longer than maybe 15 items, you might as well learn Morse. It is very easy to learn it at about 7wpm, anyone can do it rather quickly. I would never suggest anyone to learn it that slow, but it's better than nothing.
Update on the BitX20: Still no cigar :(
The receiver works, though the audio volume seems very low.
I followed the calibration instructions for the transmiter and went as far as biasing the output transistors. Problem is, I get zero drive from the microphone. I replaced one transformer and one transistor, to no avail. All components in that circuit are correct. Darn!
Gil.
Good luck with that Gil. Especially without an o-scope, debugging radio electronics can be really tough.
I have about a dozen scopes in my Ebay watch list right now, all below $100.. Big analog boat anchors, but hey, it it works, who cares...
Gil.
I've had pretty good luck tracking down problems like that with no oscilloscope. The little RF detector trick that's shown in the Elecraft K2 manual seems to work pretty well using the schematic and process of elimination.
Sent from my iPhone using Tapatalk
QuoteThe little RF detector trick that's shown in the Elecraft K2 manual seems to work pretty well using the schematic and process of elimination.
Yep, I've got one of those. It's so nice to see what the waveform looks like though...
Gil.
Quote from: gil on June 20, 2015, 07:14:31 PM
QuoteThe little RF detector trick that's shown in the Elecraft K2 manual seems to work pretty well using the schematic and process of elimination.
Yep, I've got one of those. It's so nice to see what the waveform looks like though...
Gil.
Yeah, but in your case you have no signal so you don't even have a waveform to look at, hence my comment about the detector. If I was a betting man I'd wager it's something dirt simple like a missed or cold solder joint, diode in backwards, etc. When I built my K2 I had no receive on one band, 40 meters if I recall correctly, I used the schematic and detector to eliminate entire receiver sections at a time and narrow it down to a very small part of a single section. It probably took me less than 20 minutes to find the diode where the signal stopped, and another 30 seconds with a magnifying glass to reveal the solder joint I missed on one side of that diode. One missed joint out of the thousands of solder joints I made in that K2? I didn't think that was too bad. ;D
If you have no mic signal you could use the same trouble shooting technique to locate the problem.
Yep, I just need to go through it again. I have a small guitar amp I can use to follow the path from the microphone to wherever the problem is... Once I can't hear myself anymore I'll know where it is..! On the positive side, following schematics is good schooling..
Gil.
Quote from: gil on June 20, 2015, 10:51:34 PM
...... On the positive side, following schematics is good schooling..
Gil.
I totally agree with that. Following the instructions to build a kit doesn't
really teach you much about electronics, it teaches you to mainly how to follow instructions, identify components, populate boards with those components, and solder. I've learned far more by trouble shooting my screw ups than successfully completing a kit that works perfectly the first time it's fired up. I have no doubt you'll find the problem, good luck.
Gil......what is the latest on chasing down the problem?
Hello,
I was gone for three days, but ready to get back to it now.
The receiver section seems to work fine, I hear QSOs, though the volume
is very low. Yes, I've peaked the band pass filter the best I could.
I went through the finals biasing routine with no trouble, 120mA on
receive, 300mA PTT on.
Then I got to the transmitter drive with R83, nothing!
I tested the microphone with a guitar amp, it worked. Connected the
microphone and tested again at the mic leads, played a tone through my
phone and a signal generator app near the mic, got only a faint tone at
full volume on the amp. No output on my QRP Wattmeter, even with R83
fully clockwise. No change, 300mA.
I checked Q15, 0.7V between emitter/base, 3.8V at collector/base, no
audio picked up at the collector with the guitar amp. R76 does get the
+12V when PTT. All components in the mic preamp are in the right place.
With R66 fully counter clockwise and R83 fully clockwise, I get 0.4W out
whether to tone is on or not. R66 controls carrier suppression, so I do have a carrier at least..
Next step might be to inject a tone after the mic preamp and see what happens..
I'll put a link to the manual below, with the schematic, in case anyone wants to have a crack at it..
http://qrpkits.com/files/BITX20_Assembly_Manual.pdf (http://qrpkits.com/files/BITX20_Assembly_Manual.pdf)
Gil.