Brief video covering the past couple of weeks. It looks at boxing up a radio using an old FRG-7 case, as well as repurposing a previous build for digital modes.
Your experiments and methods are absolutely awesome and very useful to people who are trying to learn. Thanks for making these videos and your website. I know you say you're not an expert, but you're much more advanced than most on the web when it comes to RF and the stages of a radio. I think you're helping a great deal of people.
The FRG-7 chassis build is very pretty. I have one nice old tube SSB rig chassis that I picked up for next to nothing, but is hopeless to get functional once more, (rock-bound rig, with separate power supply, missing, that sells for $200 online,) and I couldn't think of any interesting use for. But I may use your rig as a guide for what to do with it. Make it a custom modern rig, complete with digital modes, and amps for everything from QRPP to a couple hundred watts. (It has plenty of room for it.) Thanks for getting me thinking about it.
Wonderful! I absolutely love watching your videos. Educational and motivational. I’m still working out building individual building blocks but I’m getting there. Thank you so much for taking the time to post all your videos.
Interesting as always and inspiring. I'm building a new radio shack now I'm semi-retired...and I'm building a homebrew area in one corner so I can have a go myself. Nothing ambitious but good learning fun! Thanks for the encouragement to have a go.
Right now I have a receiver - partly based on your videos - screwed to a plank of wood. It will possibly never work as well as it does "au naturale" :-) I can't wait to be able to go to radio rallies again and search for a case like you've done there. Great job Charlie.
Very cool. I managed to get some reception out of my homebrew rig so far. Don't have an RF pre-amp yet, (not sure why I can't get my 3904 npn's to work for that.) Haven't done any work on the TX side yet and don't have any band pass filtering yet either.
Keep at it! You should need too much, if any, RF gain before the first mixer for under 10 MHz. I have not included one for several builds now. Yes you amplify the signal, but also any noise.
@@CharlieMorrisZL2CTM So far I only have an audio amp at the output, based off your design but altered for my 5v power supply. Works pretty well, I can hear my IC-718 when I transmit into a dummy load. Annoyingly my homebrew crystal filter is just slightly to tight for SSB so it sounds a tiny bit weird but I feel like that will just my rig its own personality in a way.
Thank you so much. It's pity you didn't document the process to convert that old radio. I would like rather and much appreciate the process and some obstacles during that process like final product.
Wow plenty to keep you busy there. Was thinking, when I built the data interface for my icom rather than running the audio cables to the computer I added a small USB audio dongle similar to the one you showed and a hub to the usb to serial doing the cat control. I then just had the one USB cable to plug in that did control and audio.
Great to catch up with what you've been building Charlie. Will you be covering the construction of your digital interface board that you showed at some point? I'd be interested in experimenting with that. Incidentally I've been homebrewing some crystal ladder filters - inspired by your Minimum Loss (Cohn) Filters. I've been impressed at how well they work with fairly cheap and cheerful crystals. Thanks a million for all you do and share. 73 Nick (M0NTV)
My pleasure Nick. Yes, I'll do another video on the interface at some stage. If I recall I did cover that one at some stage. I'm pleased too that the cheap and cheerful filters are going well. Not at good as commercial units, but hey, they work good enough.
Question: (Great video BTW) Other than simultaneous generation of more than one frequency (and cost), can you speak to why you use the si5351 over the AD9850 (or of like kind) given that the AD9850 generates a sine-wave and the si5351 generates only squarewaves? It would seem that you'd need to constantly be placing output filters (which don't seem frequency-agile) on them thus limiting the ability to make something like a signal-generator or a general-[continuous]-coverage receiver. Do you find problems with having square-waves "running" around the circuitry--say if you were trying to make a very-high performance receiver and needed very high dynamic range with exceptional S/N ratio? Thanks & 73...
Square waves work just fine with diode mixers. There is a good video on this on the Soldersmoke blog. See ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-WwJKxvz7qbs.html
@@CharlieMorrisZL2CTM First off thank you for responding; I thought you might’ve been a little put off by my question but it certainly wasn’t an indictment! Well I watch the video and he’s actually using very high injection amplitudes of 13 to 15 dBm where is most of the classical authors used around 7dBm. So after you watch this video did you ever consider that high of an injection? End it looks like I had it completely backwards in the to reduce harmonics you don’t want to have a continuous voltage on the switching what do you want as much of an instant transition as you could possibly get. Thanks for showing me that because I was really thinking about it completely different; that of two pure tones creating a third pure tone. Another thing I found puzzling was there when I listened to the SI 5351 on my ICOM 756 PRO II, The tone actually sounded very nice and not ratty at all even though I did not apply any filter to the output! Anyway Charlie, thank you very much I really appreciate it! 73…
Gidday Paul. The old shaft came out with the VFO. I actually had enough room to mount the rotary encoder in its place. I can't tell the difference. In a previous build I did you a flexible tube to link a rotary encoder with a shaft. That worked well and took out any play due to misalignment.
Hello Charlie Morris, I greet you from Peru, I was watching your videos some of the English language I can't understand, I have a very basic English. I wanted to ask you if you could make it a 1Mhz AM medium wave low power transmitter, from oscillation to amplification of approximately 100 watts. Thank you.
Any thoughts of using PIN diodes rather than relays? Might prove a useful side project to investgate. Appreciate the content, there is not much home brew stuff on the tube.
@@tcarney57 One data point on this discussion is the Minikits RF switching diode range, most of which are PIN diodes. I do trust Mark at Minikits, his range is carefully curated. www.minikits.com.au/BAT18
Hi Rob. Yes I did. There is a video on that from a year or two ago. They did work, but I felt for the simple projects I do that extra circuitry (RF blocking inductors etc) was not worth the dB loss across them. I'm very conscious and accept that relays introduce their own reliability issues, but I'm happy to live with that for now.
