Many thanks to SWLing Post contributor, Pete (WB9FLW), who notes that Ashhar Farhan (VU2ESE) has upgraded the BITX40 Transceiver with a Arduino Nano/Si5351 VFO:
The BITX40 is an affordable, fully assembled QRP transceiver we’ve mentioned on the SWLing Post before–click here to read more.
Thanks for the tip, Pete!
For those who receive (and send) flight data from ADS-B capable devices such as the RTL-SDR dongles or have Apps for their tablets and phones, FlightAware announced on Wednesday this change to their service:
Hi from FlightAware,
After months of development, we released a large upgrade to our back-end flight tracking engine on Tuesday. Not only did the upgrade include dozens of bug fixes and flight tracking improvements, but we added a massive enhancement for US and Canadian flight tracking — the flight status and radar data is now live with no more five minute delay! Previously, the US/Canada data feed contained a five minute delay in addition to our ~30 second processing time, but now all data is less than a minute delayed from real time. In addition to the general improvement, this yields a lot of additional benefits:
- More seamless transition between RADAR, ADS-B, and MLAT positions
- Flights will no longer transition from “Arriving soon” to “Arrived 5 minutes ago”
- Fewer estimated positions due to delayed RADAR data
Now that the radar data in the US and Canada is real-time, we’ll soon be enabling public MLAT data in the US, which is real-time just like our ADS-B data.
This is a major upgrade in data for folks in North America, and it will make using programs like PlanePlotter even more useful!
For those who might be interested in building their own dedicated ADS-B receiver, information may be found here. Of course FlightAware may be used as an online flight checking service just for tracking the progress of a given flight, which is in itself a lot of fun!
Robert Gulley, AK3Q, is the author of this post and a regular contributor to the SWLing Post. Robert also blogs at All Things Radio.
Tony Westbrook recently contacted me about a regenerative receiver kit he has designed and produced in the UK. It’s called the KRC-2. Here’s the product description:
1 – 30 MHz with band spread tuning.
Regeneration with a difference. The regeneration setting on the KRC-2 is unaffected by the receiver tuning or the antenna coupling. How do we achieve this? The regenerative stage is fixed at 10.7MHz and used as an IF amplifier. The main receiver board is extremely simple to construct using only one FET and an audio IC. Like all the KRC kits it comes with a comprehensive construction manual which brings this project well within the grasp of the keen constructor. It was referred to as “a very sensitive little receiver” by Rob Mannion of Practical Wireless. Its unconventional design and simplicity should amaze even the experienced constructor. Case size 7 x 4 x 3 inches. 6 x AA batteries supplied.
According to Tony, the kit comes with everything; UK orders are even supplied with batteries. Tony stated, “the only thing the customer needs is a soldering iron, solder cutters, etc.”
By request, Tony sent a few construction photos and three videos of the radio in operation:
Photos
Videos
Two weeks ago, through a radio preservation group, I met the son of Heathkit product designer of the 1950s-70s, Stu Sizer––”stylist, artist, maker of models, bon vivant.” His son described the discovery of a few vintage Heathkit brochures, photos, and illustrations his father kept in his family’s basement shop, many of which had been scanned at some point.
Stu Sizer––”stylist, artist, maker of models, bon vivant”––was tasked with crafting Heathkit’s user-friendly and attractive exterior designs. For many years Sizer was Heathkit’s only product designer, and was therefore often busy. “He was a great dad,” his son told me, “but he spent a lot of time in the basement proof-building kits.” He adds wryly, “Let that be a lesson to the hams of this world.”
Sizer’s son kindly shared with us the following scans and photos of his dad’s work, many of which are original drawings; the series concludes with some clippings featuring Sizer.
On Stuart Sizer
Many thanks to SWLing Post contributor, James Surprenant (AB1DQ), who shares this update to his review of the Heathkit Explorer Jr. TRF AM radio receiver kit:
With regard to the Heathkit TRF AM receiver kit, I did indeed build my LM386 amplifier.
I was planning on home-brewing it from scratch as the chip is pretty much all you need and there are various proven schematics for the circuit, but in the end I went with a small kit from Nightfire Electronics for $10 plus $5 shipping that I found on Amazon.com.
It was a bit cheaper to buy it in kit form, of course, and then there was the convenience of having all the parts in one place.
Here is a photo of the kit as advertised on Amazon…
And here is my build with the Heathkit…
I modified the kit to add a 3.5mm input jack, replacing the RCA jack that came with the kit, to make it easier to plug into the Heathkit radio.
I deliberated whether to install the audio amp into the Heathkit cabinet drilling out a couple of holes for the pot shafts. It all would have fit and I could have easily mounted the 3″ 8 ohm speaker to the back panel of the Heathkit radio. In the end, I decided to keep the radio original and mounted the amplifier board on a small piece of wood I found at a hobby store and decided to leave it all exposed. It works well, all things considered.
(Click here to view video on Facebook.)
It worked well and per my original review on SWLing Post, I feel Heathkit should have included such a little amp in the kit – it makes a big difference.
Many thanks for the update, James! That little LM386 amp kit seems like an affordable addition for any receiver lacking an amplifier or adequate audio amplification.
Many thanks to SWLing Post reader, Edward Ganshirt, who writes:
I picked up this Heathkit GR-78 at a estate/moving sale. It was in a pile of “e-waste” (you know, old vcr’s broken TVs, remote controllers, dead cell phones, etc.).
I found a container and sorted through the stuff to retrieve all what looks like Heathkit parts. The radio was disassembled and scattered about. I was able to collect all the critical components and brought the works to the sales table. The person manning the table said that was stuff they were discarding and I could have it for free but the Easter basket was $0.50.
So far I had put little time into it but was able to mechanically assemble it completely. All the fasteners holding the cabinet were missing. The rest appears to be all there but the primary side of the transformer is open and the NiCads are shorted and stone dead. The manual that I found in their recycle bin is complete and appears to gone through 3 owners by 3 sets of handwriting in the notes and comments through out the manual. If anything this looks like a CSI/forensics troubleshooting process getting into the mind of 3 different owners unsuccessful at making it work.
I will keep you posted on the progress.
WA1-LAI
More power to you, Ed! There are few things as difficult as picking up where someone else left off on a kit build. Your project is exponentially more complicated since there were three people involved and parts are scattered. Please update us with your progress.
Readers: If you have any experience with the GR-78, I’m sure Ed would welcome your input!
In reply to our post about a home brew high-pass filter, SWLing Post contributor Guy Atkins replied:
I recently purchased one of these high pass kits and an enclosure from an Australian company, and look forward to assembling it: http://www.minikits.com.au/
The price was just $14.95 USD at the current exchange rate, but I did pay extra for the matching enclosure.
It’s a 9th order Chebyshev filter at 1.8 MHz with less than 1 dB insertion loss from 1.8 to 100 MHz, and I expect it to work very well. Since it’s a kit with all parts and a PCB, it is half way between a “DIY from scratch” and a completely built commercial high pass filter.
Very cool, Guy! Looks like it’ll be a fun kit to build. Please let us know what you think of the filter once you have it assembled. $14.95 is a very fair price.