This is Retro QRP with primitive 1920's type gear. The Bruce Kelly Memorial 1929 CW Contest is a fun event held every December. Can such gear be made stable enough for 40 Meter operation?
Пікірлер: 41
@lomgshorts34 жыл бұрын
Hi Mike, Bruce was my friend (as many others were) since the day I started helping renovate the old Museum in East Bloomfield. We tore out the old wiring, the lathe and plaster walls, the plumbing, and put new ceilings, walls, wiring, plumbing in while renovating the ham shack there. I was KA2HLW then, a young kid (just 19 then) with a novice license. Between W2ICE and WA2IYA, they both got me through my General class. Before my job sent me to NC, I donated three Collins R-390A's in a rack to the museum. Between Bruce and Burt, I couldn't have had two better "Elmers" in the world. I miss them both badly. I'm glad they named the 1929 QSO Party after Bruce, he deserved it! I'm in my 60's now, still a Ham after 40 some odd years, still enjoying the ham radio service ( I do not consider it to be "just a hobby" after all the storms and hurricanes we helped out on) over the many years. Now I go by W4FJF, and still operate my original novice station now and then even though I have many transceivers and amps, and an antenna farm that covers 5 acres. Glad to see the AWA still operating, too. Do they still have the spark gap transmitter I operated one Winter day (with FCC permission)? Still have all the QSL cards I got that day - great fun, that was. Take care and 73's.
@KX4UL Жыл бұрын
Excellent video...much enjoyed! Thanks for posting. 73 OM!
@MIKROWAVE1 Жыл бұрын
I will be starting research on a QRP video to handle the early commercial approaches in the 70's.
@Tom-W7TMD2 жыл бұрын
Very fun! Thanks for sharing!
@martintavarez69919 жыл бұрын
Mikrowave, your tutorials rock! Thank you! I have viewed your Morgan Regen video hundreds of times. I find it particularly useful, and it helped me build my first working regenerative receiver. I'm goint to share some of the knowledge acquired in my 7th and 10th grade Science classes. They might as well get the passion for glowbugs. 73 and keep up the great work! Martin
@mister35mmuk9 жыл бұрын
Excellent! Very interesting and entertaining! Keep up the good work.
@VintageRadioRepair2 жыл бұрын
I started a TnT a couple years ago but never completed it. Think I'll give it another go! Thanks for the videos, awesome stuff. 73 Dave W6CPY
@MIKROWAVE12 жыл бұрын
Easy circuit but a bit dirty, but it was popular and can be tamed!
@w7hrcgreg9 жыл бұрын
Very interesting, I have always been interested in making one for the heck of it. Thank You for all the tips. 73 Greg W7HRC
@marknesselhaus43764 жыл бұрын
I doubt that my Rotary Spark transmitter would have been well received in those contests. A single key press could cover an entire band ;-)
@AlreadyThere19655 жыл бұрын
Thank you this is great stuff.
@markhodgson23484 жыл бұрын
Great work
@brum579 жыл бұрын
Great stuff Mike thanks for sharing - 73 Kevin GW4WOV
@jakemichael85866 жыл бұрын
love to see one of these transmitting on am!!!! thy used a carbon mike in line with the antenna!!!! no modulator needed!!! would like to see one on am!!!! I just love the sound of am. take care and good dx
@stephenurueta81226 жыл бұрын
Very cool!
@Isochest6 жыл бұрын
The introduction cw sounds like a lot of eastern European stations back in the 1980s
@KennethScharf5 жыл бұрын
The old ARC-5 transmitters were also MOPA types, with a Hartley oscillator, but with neutralized beam power tubes in the final. They also used CATHODE feedback, not plate. The 1920's rigs HAD to use plate feedback, because they used directly heated cathodes. (You could feed the filament voltage through another coil to get cathode feedback, and in fact the ARC-5 transmitter did that too for some reason).
@Kalkaekie5 жыл бұрын
Interesting !
@mikethees64344 жыл бұрын
Great video VE2PID been trying to get him a long time
@seanfried5583 Жыл бұрын
Ha! I remember when lots of stations sounded like that. Half of all the DX would sound like that.
@MIKROWAVE1 Жыл бұрын
Are you the Bulgarian Buzzsaw?
@seanfried5583 Жыл бұрын
@@MIKROWAVE1 HA, no, I am no one memorable. Just another CW lover, raised on old radios. WA2LKV.
@krzysztofszmel75035 жыл бұрын
lubie twoje cfilmy/pozdrawiam/
@robertpendergast26209 жыл бұрын
Fascinating-N5JYW
@stephenwilliams52015 жыл бұрын
Yes it is critical. Or the "00" send warning. keep em tight. De kv4li
@wallstreettrader1 Жыл бұрын
Great video. You should have dressed in a shirt and tie and filmed in black & white for period authenticity. 😊
@milantrcka1212 жыл бұрын
Really interesting phenomenon. Would the drift eventually stabilize at some frequency (either direction)? Really nice drift fix; took a fair amount of time to tame it. Inasmuch as it can be controlled by the tuning the grid tap, is it known what the root cause of the the frequency drift is? Component drift with temperature (caps, copper resistance, tube)? Space charge in the tube?
@daveschmittle36284 жыл бұрын
Mike, with this type of transmitter would I have to use the old type caps? The tube I'm using is a 27 type which 250 volts. Could I use modern caps as long as they are within the plate voltage or do I need to go older and larger?
@MIKROWAVE14 жыл бұрын
Dave, I hope you are able to build up a transmitter for the 1929 Bruce Kelly Memorial contest coming up soon in November. Any era parts can be used as long as the tube type was on manufacture in or before 1929 and the circuit was known to have been used. For instance a UX227 could be replaced by a a type 27, even if it were manufactured in 1947.
@daveschmittle36284 жыл бұрын
I'm trying to get it done. I'm having issues locating a power transformer I can use for the 2.5 volt filiment for the 27 tube. I want to build my own power supply. Hopefully I'll have it done. How precise can the tnt tune on a band? Do you have any good schematics for a vintage period powersupply?
@MIKROWAVE14 жыл бұрын
Sometimes you can find a 230VAC 5V job that you simply run on 120. Also consider using half of AC a 5V Center tapped transformer. Finally 2 type 27s filaments can be connected in series for 5V.
@wa8lhb5399 жыл бұрын
Mike, I've heard there is no such thing as a dumb question. But, I'll ask one anyway. From where do you obtain the -90V bias shown in the circuit at 03:54 from the power supply shown at 11:10? I hope to enter this years contest using your MOPA design. I have all of the parts. Thank you. 73 Tim WA8LHB
@MIKROWAVE18 жыл бұрын
+WA8LHB Hi Tim, The Bias supply is from a backwards 12V transformer connected to a 6.3V winding of the main power transformer in the power supply. That gives 60VAC which is run to a small bridge rectifier that feeds an electrolytic (positive side down to ground) and then a 100K potentiometer giving a 0 to -90V bias supply.
@stephenwilliams52014 жыл бұрын
Oscillator or theremin ?
@MIKROWAVE14 жыл бұрын
Um. Oscillator with flavor?
@mohinderkaur66715 жыл бұрын
Dont touch the +1000 DC on the PA tube
@user-dh1kq3eh8q5 жыл бұрын
Bravo 73 milan yu1qg
@allanegleston138 жыл бұрын
thanks for sharing . de kf6uxj
@K1OIK9 жыл бұрын
I can't build but are you selling? VE2PID lives on 40 meters