Serving the worldwide community of radio-electronic homebrewers. Providing blog support to the SolderSmoke podcast: http://soldersmoke.com
Sunday, December 30, 2018
HT-37 Choke Failure -- Why did this happen? What is your diagnosis?
Look, it has been 60 years, so I'm not looking for my money back or anything, but having just repaired the LV power supply choke on my very venerable Hallicrafters HT-37, I started thinking about how and why it failed.
Clues:
-- I found it with four of the windings broken, with the eight broken leads kind of sticking out of the winding wrap.
-- The four broken leads were on the outside of the winding (thank God!) an were at the part of the winding closest to the chassis and the back of the cabinet. (See picture below.)
-- There was evidence of burning on at least two of the leads.
-- The choke is located in the extreme back corner of the chassis, near the back of the cabinet.
-- The paper and cellophane wrapping around the windings was a bit deteriorated.
So, what is your diagnosis? What happened to cause the choke to go open?
Saturday, December 29, 2018
KC1FSZ's Peppermint III Homebrew BITX with Mods
Hi Guys:
I had some time over the holiday to finish off my second
scratch-built rig. I am very thankful that I got the work done on these
projects before I read Pete's "Don't Build It" diatribe. That
would have been very demoralizing. :-)
Scratch build #2 (called Peppermint III) is still fundamentally
BITX although I've made changes this time around. I've
switched to ADE-1 mixers with LO ports driven by adjustable gain buffers
(ala N6QW LBS). I've noticed that performance can be improved a lot if
you can buffer/tweak the LO levels of the VFO and BFO (particularly carrier
suppression on TX). I did W7ZOI TIAs in the IF chain. I've also
taken the shielding/layout of the finals more seriously and have been able to
dial up the power a lot (I did the KB1GMX thing with cutting off the drain pin
on the IRF510 and using the tab). The software is also greatly improved
and now supports LSB/USB modes as well as software-driven PTT control for
RTTY/FT8 and the hooks for my poor man's panadaptor. I've been working
lots of stations on QRO.
Total build time was about three months (half the time of #1)
and the layout came out much smaller than before. I made a trip over to
Williams/Sonoma after Christmas and picked up the 2018 edition of the
Peppermint Bark candy tin on discount and I think I can make it all fit.
More to follow ...
Happy New Year and 73s,
Bruce KC1FSZ
Friday, December 28, 2018
HT-37 FIXED -- Thanks for all the support
Don't worry-- I covered it with tape |
It worked. My AADE L/C meter won't measure up into the full Henry range, but the choke was no longer open and the resistance looked right (about 230 ohms).
I put it into the HT-37. It works. I had a long rag chew with AE2EE -- a guy who really knows his boatanchors. He said it sounded great. This contact was like icing on the cake. TRGHS.
Thanks to everyone who wrote in with offers of parts or suggestions on how to acquire a suitable replacement.
Special thanks to Steve Murphy, N8NM who removed the LV choke from a junker HT-37and mailed it to me JUST AS I WAS LEARNING THAT THIS REPAIR WOULD WORK. I feel bad about putting Steve to the trouble. I blame the shut-down. Idle hands are the devil's workshop. And that broken HT-37 was bothering me.
This was a very satisfying repair. It was great fun to put the old rig back on the air. And I did it without injuring myself. Straight Key Night is right around the corner.
Terminal strip for newer caps. Repaired choke went to the two ends of the strip. |
Thursday, December 27, 2018
W7RLF Homebrews a Receiver -- FB!
Ryan W7RLF has joined the small and elite group of radio amateurs who have homebrewed a receiver. And it is a receiver filled with soul, juju and mojo; the project was inspired by Wes Hayward and Farhan, and used components from Hans Summers. Congratulations Ryan and thanks for all the work you did in documenting your experience.
Who will be the next intrepid ham to join the homebrew receiver club?
Hello Sirs!
This month I read Wes Hayward's post on the history and heritage of DC receivers in ham radio and it brought a lingering interest to a head. I had to build one. I run the BITX40 and uBITX group on Facebook, and I posted to the other hams there: Which DC receiver should I build? Farhan recommended his DC40. Mind you, I've never homebrewed a radio before, so this is all new territory for me.
I did build it, and it does work. It also uses QRP Labs stuff from our friend Hans Summers. This thing has a lot of QRP heritage :) I documented it every step of the way including all of my dumb moves and things I got wrong, and my desire is to inspire others to try homebrewing the way Wes, Farhan, Hans, and you YOU GUYS have inspired me to try it. I am hooked, of course! Here's a link to my blog to Part 1:
It's a four part series (unofficially 5 really) with 8000 words to it, and I hope you guys enjoy it and I'd be ticked pink if was worthy of mention on your show. Here's a video of it too:
73 to you both and I wish you the best!
Wednesday, December 26, 2018
Ghost Ship: Oscar 11 Tumbles Through Space
First -- Happy Boxing Day to all our UK and Commonwealth friends.
Oscar 11 is a UK-built amateur satellite launched in 1984. It has been dead (well, almost dead) for many years. But when the sun shines on the solar panels, it wakes up and transmits. I've been able to hear it and -- more usefully -- see it on my RTL-SDR HD-SDR receive system. My antenna is my re-born (from the Dominican Republic) three element homebrew 2 meter cubical quad (see pictures below).
I'm sorry the video is a bit out of focus, but you can clearly see the trace of the signal from the satellite. Realize that my HD-SDR software is about 10 kHz off calibration. You can see the Doppler shift, and you can see the signal fading in and out as the old satellite tumbles through space. Any ideas on what the other signals seen off to the side are? Is anyone else listening for Oscar 11?
https://amsat-uk.org/satellites/telemetry/uosat-2-oscar-11/
https://en.wikipedia.org/wiki/UoSAT-2
http://www.dk3wn.info/p/?cat=47
Monday, December 24, 2018
Saturday, December 22, 2018
Tuesday, December 18, 2018
All I want for Christmas is... an HT-37 L25 Choke-- 9 Henries at 135 ma
Following my own advice to prepare for Straight Key Night, I tried to fire up my venerable Hallicrafters HT-37 transmitter. It didn't work. I quickly determined that none of the oscillators were working, so my troubleshooting focused on the power supply. Sure enough, the choke in the low voltage power supply is open. That's bad.
I briefly considered giving up on this old rig. I don't really like working with tubes anymore. And this thing is very heavy -- a real beast. DX-100-like in its heaviness. It can be hazardous to your health just moving this thing around. Opening up the case is not easy. And there are nasty voltages in there....
But I have had this transmitter since 1973 or 1974. I have fixed it many times, in several countries. I got it from a member of the Crystal Radio Club when I was a kid. There are parts given to me by Pericles, HI8P in the Dominican Republic. I used it to transmit through Russian satellites. That transmitter is like an old friend. I just can't give up on it.
So I need to replace or repair the choke. Is there anyone out there who has a junker out in the garage or some other source of L25? Or does anyone know of a business that could rewind the choke. Please let me know. I have decided to leave the rig on the bench until I get this thing fixed (it is too heavy to move multiple times!)
It it Hallicrafters Part Number 056-300259. L25 -- 9 Henries at 135 ma. Help!
Saturday, December 15, 2018
SolderSmoke Podcast #208
SolderSmoke Podcast #208 is available:
http://soldersmoke.com/soldersmoke208.mp3
15 December 2018
Pete and the California fires
Bill goes to Brooklyn
2 meter simplex
A return of the trivial electric motor
Audio from Mars
HF Conditions -- a real mixed bag
Pete looks back at 2018 -- The Year of the SSB Transceiver -- Lessons Learned
Hans Summers, the QSX and the virtues of SDR
W7ZOI's DC Receiver Retrospective
The 1972 Solar Flare and the Vietnam War
SHAMELESS COMMERCE: Buy your gifts through the Amazon link to the upper right.
Consider SolderSmoke the book as a gift. Visit Pasta Pete's for cooking ideas.
Don't Build It! Sage -- but unexpected -- advice from Pete.
Straight Key Night approaches.
Book Reviews:
--"What is Real?" (Quantum Physics)
-- RHdb by K6LHA.
Movies
"Bohemian Rhapsody"
"First Man" (Not yet!)
MAILBAG:
Steve G0FUW
Ed KC8SBV
Friday, December 14, 2018
Another AMAZING Homebrew Vacuum Tube (Valve)
I feel a moral obligation to put these projects on the blog every time I see one. It just seems like the right thing to do. Great work on the Pilotron. Great workshop video also.
Wednesday, December 12, 2018
Built-in Spectrum Analyzer in Hans Summers' QSX Rig.
I agree completely with the e-mojis. Wow! Cool! I love it!
Hans Summers is a genius.
This is almost enough to make me get with the program and embrace SDR.
Hans has done what seemed to have been impossible: true homebrew with SDR.
Sunday, December 9, 2018
First Audio From Mars
How long will it be before NASA starts getting critical comments on the audio quality, along with very confident statements about how to change the audio settings on the menu? Well, at least they have "presence."
The Elser Mathes Cup awaits a winner!
Monday, December 3, 2018
A Beautiful Launch! Watch the Video
Today's SpaceX Falcon 9 launch of Farhan's Exseed Satellite was really spectacular. Congratulations Farhan! Really inspirational stuff.
Now we wait to hear the bird. If I have loaded the orbital information correctly, I should have my first chance this evening. I have my antenna positioned.
Sunday, December 2, 2018
DON'T BUILD IT! Sage Advice from Pete N6QW: Why You Should NOT Build an SSB Transceiver
Be sure to read the comments. Especially my comment. And Pete's response.
https://n6qw.blogspot.com/2018/11/2018-year-of-ssb-transceivers_27.html?showComment=1543673593869#c2528546290216719692
Launch Day! Godspeed Exseed! 1:31 pm Eastern time. Video links here.
Farhan posted this message and the above video to Facebook today (I have the video cued up to around the 5 minute point):
We are all set for the launch of ExseedSat... There are two tiny switches at the bottom of the satellite that keep the satellite switched off while it stays in it's container. Once the satellite is ejected, the switches are released and the satellite wakes up.
There are 36 satellites on this launch, some belong to close friends in the satellite fraternity. We wait for all the satellites to drift out and after 45 minutes, the antennas are depolyed and we will start beeping signals home.
Here is a test of that process. You can skip to the fifth minute to watch the antenna depoly .
I really like the tape measure antenna. This recalls the earliest OSCAR satellites. And let's not forget that OSCAR 1 also launched from Vandenberg. So there a lot of good tradition flying with Farhan's bird.
Press reports indicate a launch time of 1:31 pm Eastern time today. I think you can watch it live through the video window below. Or try this link:
https://www.youtube.com/watch?v=Wq8kS6UoOrQ
Saturday, December 1, 2018
Cubesat Launch Now Scheduled for Sunday Morning (California time)
Here is an update from the San Luis Obispo News:
It kind of makes you wish you were out there...
https://spacenews.com/dedicated-rideshare-falcon-9-launch-raises-satellite-tracking-concerns/
https://www.theverge.com/2018/12/1/18114894/spacex-falcon-9-reusability-sso-a-mission-rideshare-satellites
Friday, November 30, 2018
Totally Absurd -- Farhan Being Questioned in a Police Station
I walked into the shack this morning hoping to read good news about the InSight landing and the impending launch of Farhan's satellite, but instead I found this message from Farhan in a police station. This is really absurd and disheartening. Someone (not Farhan!) altered the Indian flag and put it into an image of Farhan's CubeSat. So with 24 hours to go before the launch, our friend Farhan finds himself in a police station.
Stay strong Farhan! You have a lot of support around the world.
Wednesday, November 28, 2018
Sunday, November 25, 2018
Falcon 9 Cubesat Launch Now Set for Wednesday
It looks like the Falcon 9 with Farhan's CubeSat is not scheduled to launch this Wednesday between 1030 and 1100 West Coast time. Above you can see a similar launch.
https://www.sanluisobispo.com/news/local/article222135690.html
Saturday, November 24, 2018
Friday, November 23, 2018
The Max Valier Satellite Flies Over, Sending CW
I understand the launch of Farhan's CubeSat has been delayed a few days. That's the way it works in the rocket launch biz --patience is required. In the meantime, I've been practicing with my receive system. Today at 1000 local the Max Valier satellite flew to my west. It rose 78 degrees above my horizon to the W NW. I left my three element quad pointed in that direction and waited for the satellite (which had been launched from India) to fly through its pattern.
The CW beacon was quite strong, very visible and audible through my RTL-SDR dongle and HD-SDR software. You can see it and hear it in the video above. There is something quite charming about this very personal Morse message coming down from orbit and then passing through all that digital technology.
More info on the satellite:
"Max Valier Sat" is an amateur satellite built in cooperation by:
- "Max Valier" High School in Bolzano/Bozen (Italy)
- OHB System AG from Bremen (Germany)
- Max Planck Institute for Extraterrestrial Physics from Garching (Germany)
Its main payload is an X-Ray telescope devised and made by MPE. Data generated by this detector will be transmitted, together with housekeeping data, over an amateur radio link with frequency 145.860 MHz.
A second payload is an amateur radio beacon transmitting a message in Continuous Wave. The beacon's frequency is 145.960 MHz
"Max Valier Satellite" was launched by the Indian Rocket PSLV-C38 on June 23, 2017 at 9:29 am IST (05:59 am CET) from Satish Dhawan Space Centre.
More tech details:
Regarding the CW beacon:
And who was Max Valier? Quite an interesting fellow:
Beacon by Holger Eckardt DF2FQ:
- Transmit frequency is 145,960 MHz (IARU and ITU coordinated).
- Modulation is CW:
- Duration of one dot is 114 ms.
- Duration of one dash is 342 ms.
- Interval between words is 1881 ms.
- Interval between repetitions of the message is 6000 ms.
- The beacon transmits Max Valier Sat's call sign and a greeting message.
- Transmitting power is 500 mW.
And who was Max Valier? Quite an interesting fellow:
Max Valier in his Rocket Car in 1930 |
Saturday, November 17, 2018
From BITX to SpaceX: Falcon 9 To Launch Farhan's Cubesat on Monday (video)
- SpaceX will live-stream the launch as well on their YouTube stream. Also - this will be the first SpaceX booster to fly three times, and the first to launch from all three SpaceX pads.
https://forum.nasaspaceflight.com/index.php?topic=46756.0
Special thanks to Dave Bamford for the BITX to SpaceX line!
Friday, November 16, 2018
Wednesday, November 14, 2018
W7ZOI: Direct Conversion Receivers -- Some Amateur Radio History
http://w7zoi.net/dcrx68.pdf
Farhan and Pete WB9FLW alerted me to this wonderful article by Wes Hayward, W7ZOI. I guess my interest in DC receivers must have been noticed by the Google algorithm because I am bombarded by ads extolling the virtues of "Zero IF." Hey Google -- I'm already a believer! I was converted by W7ZOI's 1968 article in QST. And my belief in the technique has been greatly reinforced by his November 2018 50th anniversary article.
There is so much good stuff in Wes's look-back piece. The travails of trying to write for QST are presented very well. And we learn that none-other-than Doug DeMaw himself is responsible for the use of the word "presence" in describing amateur radio audio.
This article has inspired me to take a new look at the DC receiver I built last winter. Mine needs some work. I think it is kind of deaf. It could probably benefit from a diode ring detector. But it already has presence.
http://w7zoi.net/dcrx68.pdf
Thanks Wes. And thanks to Farhan and Pete for the heads up.
Tuesday, November 13, 2018
1972 Solar Flare Caused Naval Mines to Explode
There are reports out this morning that a big solar flare in 1972 caused naval mines placed by the U.S. off the coast of Vietnam to explode.
https://www.livescience.com/64062-mines-solar-storm-1972-vietnam.html
https://www.colorado.edu/today/2018/11/12/1972-solar-storm-triggered-vietnam-war-mystery
Background info:
https://oraprdnt.uqtr.uquebec.ca/pls/public/docs/GSC418/F1929448428_Solar_Superstorm__Astronomy_Sept_2008.pdf
I remember this solar event. It caused aurora near New York City:
https://soldersmoke.blogspot.com/2009/09/carrington-flares-aurora-where-were-you.html
https://www.livescience.com/64062-mines-solar-storm-1972-vietnam.html
https://www.colorado.edu/today/2018/11/12/1972-solar-storm-triggered-vietnam-war-mystery
Background info:
https://oraprdnt.uqtr.uquebec.ca/pls/public/docs/GSC418/F1929448428_Solar_Superstorm__Astronomy_Sept_2008.pdf
I remember this solar event. It caused aurora near New York City:
https://soldersmoke.blogspot.com/2009/09/carrington-flares-aurora-where-were-you.html
Monday, November 12, 2018
Getting Ready for Farhan's Satellite (videos)
I've been getting ready for the November 24 launch of the CubeSat that Farhan and his friends in India built. I started out with my trusty Drake 2-B and a Hamtronics 2-to-10 downconverter, but I quickly switched to an RTL-SDR dongle and HD-SDR software. My 3 element quad antenna is visible in the first video. So far, I am using the Armstrong method to turn the antenna.
In that first video I keep saying that I am waiting for AO-71. In fact is was AO-73, the "FunCube" from the UK. I think it is similar in power and antenna configuration to Farhan's satellite, so I think we are almost ready for launch.
(Any ideas on what that mysterious pulsating sig in the satellite passband signal is in the first video?)
Monday, November 5, 2018
Pete N6QW Rejuvenates the Atlas Twins with an Arduino and an Si5351
Pete Juliano N6QW has turned his attention to the Atlas Twins, a nice single conversion multiband rig. Pete has used an Arduino/Si5351 to replace the analog oscillators in the old Atlas. This improves stability and allows for USB/LSB operation.
Pete very graciously kept the old analog circuitry in the rig, allowing the Atlas to be returned to its pristine analog state at some time in the future. Pete also made some very kind comments about the surprising stability of the original analog oscillator circuitry.
Check out Pete' site for more details:
http://n6qw.blogspot.com/2018/11/2018-year-of-ssb-transceivers.html
Saturday, November 3, 2018
Oliver Heaviside
https://hackaday.com/2018/10/30/oliver-heaviside-rags-to-recognition-to-madness/#more-330784
Like many of the giants we looked at, Oliver definitely had his problems, and didn't end well. But he deserves a lot of respect and credit for his many innovations and discoveries. I didn't know that he is the one responsible for those 88 mH coils in my junk box.
Saturday, October 27, 2018
SolderSmoke Podcast #207 -- 15 mtrs, 60 mtrs, Giants of Radio, Cubesats, Pete's rigs, SDR MAILBAG
SolderSmoke Podcast #207 is available:
http://soldersmoke.com/soldersmoke207.mp3
-- Giants of Radio
-- Pete on 15 Meters
-- Bill on 60 Meters with the uBITX
-- Pete's Sudden and Heath Filter Transceivers
-- Cubesats to orbit! To the moon! And to Mars!
-- Bill rebuilds his 2 meter "Ray-Gun" Quad (for Farhan's Cubesat)
-- Homebrewing Variable caps and stockpiling NP0
-- My "by ear" Minimal Discernible Signal Technique
-- Thoughts on Direct Sampling SDR and the Radio Art
MAILBAG
-- A request for feedback from GQRP
-- G4WIF reports G3ROO on UK TV with spysets
-- VU3XVR builds FB rig from EMRFD
-- M0KOV Charter member of the 3 Scratch-built BITX club
--KD4PBJ's PTO Turtle DC Receiver
-- AB1OP builds Pete's LBS receiver and gives us a new acronym: SITB
-- KD4EBM -- Thanks for the scanner Bob!
-- A possible sponsor from California...
-- Pete's dream neighborhood...
Friday, October 26, 2018
Homebrewing Your Own Variable Capacitors
It is people like Jeremy Cook who will save us from total domination by DDS and PLL "oscillators" and their whimpy little "rotary encoders."
Tuesday, October 23, 2018
uBITXs Doing Very Well on 60 Meters -- with Boris and Natasha
Last Saturday something told me to get on 60 meters. TRGHS. So I stepped out to the carport and tuned the doublet to 5.3 Mhz -- and I'm really glad I did. There was a lot of activity on the band, all very friendly. Channels 1 and 2 seem to be especially popular watering holes.
Channel 3 might be getting a bit more digital use, but a very interesting group called the "Moose and Squirrel Net" meets there at noon (east coast time) on Saturday on SSB phone. This group is kind of a spill-over from the Old Military Radio Net that meets early on Saturday morning on 3895 kHz AM. Because many of the old military radios can't tune on half kHz increments, the "Moose and Squirrel" group used channel 3 which is the only U.S. 60 meter channel on a whole integer kHz frequency (5357.0 kHz). Moose and Squirrel takes it name from the old Boris and Natasha Cold War cartoons that many of us watched as kids. Natasha Fatale and Boris Badinov. Cold War era military radios, get it? Good stuff. Many of the guys on the M&S net commented on how nice the uBITX sounded. I was running it through my .1kW CCI EB63A amplifier.
One of my nicest contacts was with Joe WA2EJT. He told me that he too has a uBITX. He said he bought the rig in part because of he liked the fact that Farhan was giving the work on the toroids to some ladies in Hyderabad who normally do sewing. Joe said he liked the look of the uBITX board so much that he decided to put his board on top of the chassis instead of inside it. That is exactly what I had done with my first BITX 40 module. See the pictures of Joe's rig.
Three cheers for the uBITX!
Boris, Natasha and "Fearless Leader"
Monday, October 22, 2018
Ian Keyser G3ROO on UK TV with his Spy Set Rigs (video)
Me at the keyof one of Ian's spy sets -- ten years ago? |
https://www.itv.com/news/meridian/2018-10-19/daring-spies-who-broadcast-from-behind-enemy-lines/
And here is Tony Fishpool's report on their excellent adventure at Friedricshaffen Hamfest 2018.
http://www.fishpool.org.uk/friedrichshafen.htm
Here are some of the SolderSmoke blog posts on the activities of Ian and the Dover Constructors Club.
https://soldersmoke.blogspot.com/search?q=G3ROO
Sunday, October 21, 2018
Saturday, October 20, 2018
Pete's New Transceiver with Heathkit Filter and WSPR (Video)
Another beautiful rig from Pete. Inspiration for the winter building season. More info on his blog:
http://n6qw.blogspot.com/
We hope to discuss this and other projects in the next SolderSmoke podcast, hopefully next Saturday.
Wednesday, October 17, 2018
M0HYT's Through-Hole (No Surface Mount) uBITX
That's the spirit! I like how Peter M0HYT took the uBITX schematic and built his own, his way. When you build the rig yourself, if problems arise (spurs, harmonics getting past filters) you are in a much better position to fix the problem. I'm afraid that sometimes those buying an already-assembled board just feel aggrieved if the purchased item is not fully within specs.
M0HYT posted this to the BITX20 group (this past summer):
I have just built a uBITX with standard components (no SMD's) from scratch on a PCB I designed - it works well. I have now designed another PCB which incorporates the Arduino NANO and the the Si5351 shield and I'm just waiting for the PCB's to arrive and then I will start assembling. I made some changes to the circuit to allow for a dynamic microphone and the use of screened TOKO cols for the 30MHz lowpass filter, I also changed the coupling arrangement to the 45MHz filter.
I have attached a picture of the original PCB and a PDF of the new layout incorporating the Arduino and Si5351
Maybe one day I will play with SMT but for now standard components are still easily available !
73's - Peter M0HYT
Saturday, October 13, 2018
Chinese AMATEUR Satellites ORBITING THE MOON! Radio Amateurs Receiving Images
This is really amazing and deserves more attention than it has been getting.
http://www.spaceflightinsider.com/organizations/china-national-space-administration/contact-lost-with-chinas-dslwp-a1-lunar-microsatellite/
https://twitter.com/bg2_cry
https://twitter.com/bg2bhc
https://space.skyrocket.de/doc_sdat/dslwp-a.htm
https://destevez.net/2018/06/dslwp-b-detected-with-7-element-yagi/
Tuesday, October 9, 2018
Falcon 9 Launch, Landing and Sat Deployment Video
Very cool video from Space X. I like how they have the time-line along the bottom and the telemetry in the upper right. This is the first time they brought a first stage back to Vandenberg AFB. I hope we get to watch the launch of the Indian Cube-Sat in November.
Monday, October 8, 2018
VU3XVR's EMRFD TIA HB TRANSCEIVER
Ram did a beautiful job on this 40 meter rig. You can read about this project here:
https://vu3xvr.blogspot.com/2018/10/homebrew-5-watts-cw-transceiver-using.html
Sunday, October 7, 2018
Stockpiling Parts for Analog Oscillator STABILITY
Doug DeMaw taught us that a key contributor to analog oscillator stability is the use of NP0 capacitors. As part of my effort to maintain the ability to produce analog, discrete component, coal-and-cap, chip-free oscillators, I recently went out onto the internet in search of an assortment of NP0 capacitors. Nightfire Electronics had just what I needed. I took their assortment and put it in a parts box for easy access.
Saturday, October 6, 2018
Radio Astronomy Knack!
This video has so much of the kind of stuff that interests us: roadkill antennas. 3D printers. Arduinos. Raspberry Pi, And of course, RADIO ASTRONOMY.
And the Thought Emporium guys have a lot of other great project videos on their YouTube site:
https://www.youtube.com/channel/UCV5vCi3jPJdURZwAOO_FNfQ
I feel myself being pulled back into SPACE. First there was Farhan's new satellite, now this. Last weekend I finished a 3 element quad for 146 MHz. In a fit of nostalgia I used the same copper tube elements that I used to communicate with the MIR space station from the Dominican Republic in 1995. They have good JuJu. And Mojo. TRGHS. More on this later. Tune UP!
Sunday, September 30, 2018
Wednesday, September 26, 2018
The Triple Scratch-Built BITX Club -- Do you qualify for membership?
OK, so how many of you guys can join Steve M0KOV and me in the Triple Scratch-Built BITX Club?
Bill
Below are my three Bitx builds.
1st build.
Closely follows Farhan's original 20m design but I soon changed the VFO for an arduino/ad9850. It was a fast, get me on the air build, it worked, but not well.
The output amp was built on a separate board as part of its exorcism.
2nd build.
This was to be my two band Hill Topper, we don't have mountains in Yorkshire. Built with separate stages slotting into the eddystone box to save space and to help with shielding. The receiver worked very nicely, the output kept blowing irf510's. I later found that they were a hopeless batch. Very hard to work on.
3rd build. Big is beautiful. Arduino/si5351 straight into the modulator and into the mini-circuit mixer through a driver as discussed. Norton feedback RF preamp and a ne5532/lm386 AF amp. At the moment it's on 80m but it did start on 40m. It's still a work in progress and I will have to sort that soldering iron band change.
73 Steve M0KOV
Sunday, September 23, 2018
Freethink YouTube Channel
Lots of really nice, inspirational videos here:
https://www.youtube.com/channel/UConJDkGk921yT9hISzFqpzw
Farhan's Satellite
The launch is set for November 24, 2018 from California. It will be in a polar orbit. The beacon will be on 145.90 MHz. Farhan says an RTL-SDR Dongle should do the trick. I plan on building several receive systems and an appropriate antenna.
https://telanganatoday.com/a-blessing-for-the-small-guys
https://www.thehindu.com/news/national/other-states/odisha-man-team-builds-private-satellite/article24963338.ece
https://www.timesnownews.com/technology-science/article/instagram-now-lets-you-shop-directly-from-stories-explore-tab-heres-how/286276
I don't think Farhan's group is connected to this group, but this short video does a nice job of explaining the potential of CubeSats.
FROM Prasad VU3YFD:
Hi my friend's information to all about a man's " A DREAM COME'S TRUE " in " VU " LAND with his hard work & to the whole team.. we can say ......FANTASTIC ..... no other words to express from my side but i ENVY on their hard work's.. hi hi .de vu3yfd,prasad
AMSAT-UK
IARU Amateur Satellite Frequency Coordination
List of Sats formally submitted
ExseedSat Updated: 10 Aug 2018 Responsible
Operator Ashar Farhan VU2ESE
Supporting Organisation Exseed Space Innovations Pvt Ltd
Contact Person afarhan@gmail.com.nospam
Headline Details: The ExseedSat is a 1U cubesat that will provide a multifunction UHF/VHF NBFM amateur communication satellite. It will have various configurable modes, including: • UHF to VHF, single channel, narrow band FM transponder with CTCSS, 67 Hz squelch • Power output selectable between 1 watt and 0.5 watt • Digipeat feature with APRS on UHF uplink nd VHF downlink • Melody mode : It will play a simple melody of a few notes on special occasions or events. This will interest students outreach. • We expect this satellite to have a life of two years, depending upon how long the battery lasts and when the satellite de-orbits naturally. Planning a SpaceX launch from Vandenberg in October 2018 **The request has now been updated to include only a U/V transponder/digipeater** **The following frequencies have been coordinated: 145.900 MHz for repeater and digipeater downlink and for telemetry and 435.340 MHz for repeater and digipeater uplink**
Application Date: 19 Jul 2018 Freq coordination completed on 10 Aug 2018
Operator Ashar Farhan VU2ESE
Supporting Organisation Exseed Space Innovations Pvt Ltd
Contact Person afarhan@gmail.com.nospam
Headline Details: The ExseedSat is a 1U cubesat that will provide a multifunction UHF/VHF NBFM amateur communication satellite. It will have various configurable modes, including: • UHF to VHF, single channel, narrow band FM transponder with CTCSS, 67 Hz squelch • Power output selectable between 1 watt and 0.5 watt • Digipeat feature with APRS on UHF uplink nd VHF downlink • Melody mode : It will play a simple melody of a few notes on special occasions or events. This will interest students outreach. • We expect this satellite to have a life of two years, depending upon how long the battery lasts and when the satellite de-orbits naturally. Planning a SpaceX launch from Vandenberg in October 2018 **The request has now been updated to include only a U/V transponder/digipeater** **The following frequencies have been coordinated: 145.900 MHz for repeater and digipeater downlink and for telemetry and 435.340 MHz for repeater and digipeater uplink**
Application Date: 19 Jul 2018 Freq coordination completed on 10 Aug 2018
Read The Hindu story at https://www.thehindu.com/…/odisha-man-t…/article24963338.ece
IARU information http://www.amsatuk.me.uk/iaru/formal_detail.php…
Gurudatta Panda VU3GDP http://gurudattabam.blogspot.com/
Ashhar Farhan VU2ESE http://hfsignals.blogspot.com/
Tnx cu agn de vu3yfd,prasad
Saturday, September 22, 2018
Pete's New Sudden Transceiver
Check it out! Note the Juli-yellow front panel color. Featuring FT-8 and WSPR capability. Go Pete!
http://n6qw.blogspot.com/2018/09/2018-year-of-ssb-transceivers_14.html
will carry a live feed of the launch