I bought a used HRO in 1957, at the age of 12. I had a newspaper route, and one of my customers sold it to me. The HRO came with 4 band plug-ins (if I remember correctly). USSR launched Sputnik on October 4, 1957, and I immediately took my HRO to art class, so we could hear Sputnik beep-beep-beep on 20 MHz as it passed overhead, every 90 minutes or so. Of course, I was given a lot of positive feedback, and the shock of USA playing 'catch-up' to the USSR, plus the money that poured into education, pushed me into electrical engineering.
My understanding was it was not difficult to hear, and I totally share your comment on Education and Engineering BOOM it forced on the US to wake up and fortunately, catch up in the Space Race. Now Elon is holding up that baton... I was 3 years old, so greatly benefited on the Science and Engineering boost. I has a Transistor and Tube radio business by 5th grade, and a mentor who was a WW2 Vet at his TV Repair shop in NNj. Read every Radio/Electronics book in Elementary school, met some Hams and got my license thru HS. Went to Bradley University with my best friend from the club, and became an EE, now still using my Ham Radio skills every day at 70, qualifying the latest 400 G Optical Networking equipment EMC, Laser and Electrical Safety certifications. I don't have an HRO, but still have my college National Radio NCX-200, NCX-3' full NCX-5 station an an NCL-2000 in restoration. 73s, Hilary W4HDL
Not noted in the Bottom View tour of this excellent Video, was the very wise modification was clearly marked as an OA2, OR VR-150. a GREAT improvement in powering the VFO and likely BFO. Without this additional regulation definitely improved this SSB demo not drifting much. Very risky leaving ANY waxies in vintage equipment at all. They absorb humidity, and the Paper dielectric has traces of Sulphur I believe, that leads to the potential damaging DC leakage. The worst case is always where a coupling cap has very high POSITIVE voltage on it, and feeds a next stage megohms input Grid at maybe -5 to -50V. This slams that tube into saturation, and may damage the plate, or if you are truly unlucky, burn out a rare Transformer's winding! These radios came out of pioneering work of George Millen and Charles Grammer at ARRL in the 1930,s, and the planetary reduction drive invented by a famous Mechanical Engineer at National Radio. I read that the Intercept antennas at Bletchley Park had an 807 power tube for Distribution Amplification, feeding the rooms of HRO's! HRO was the moniker given as the US Military purchasing - after a successful evaluation, the Govt said make as many as you can and don't stop until we tell you. HRO stood for Hellova Rush Order.. Also the coil packs could be set up for Bandspread, and responsible, along with those tubes with caps - isolating the Grid leads, allowed very wide frequency ranges AND excellent stage isolation due to no bandswitch/wiring. 73s, Hilary W4HDL
Great radio, and sounded good, back in the 60's had that 19 Set as on your bench followed by 1155, it was totaly rewired in purple wire, but worked fine, then HRO. That was a while back 😀 enjoyable video thank you for the visit to the past.
A brilliant classic vintage receiver Justin. A friend of mine had one when I first started getting into listening to Amateur radio and I was very impressed. A must for the shack and this one looks in excellent condition. 73...David M0DAD.
What's the horizontal valve that's been added under the chassis? First receiver I had back in my youth - over 50 years ago. You know an HRO owner from the callouses that they develop on their hsnds changing the coil packs ! It's just pre-war and very many were used in listening posts feeding intercepts to Bletchley Patk.
A very wise modification was clearly marked as an OA2, OR VR-150. a GREAT improvement in powering the VFO and likely BFO. Without this additional regulation definitely improved this SSB demo not drifting much. Very risky leaving ANY waxies in vintage equipment at all. They absorb humidity, and the Paper dielectric has traces of Sulphur I believe, that leads to the potential damaging DC leakage. The worst case is always where a coupling cap has very high POSITIVE voltage on it, and feeds a next stage megohms input Grid at maybe -5 to -50V. This slams that tube into saturation, and may damage the plate, or if you are truly unlucky, burn out a rare Transformer's winding! These radios came out of pioneering work of George Millen and Charles Grammer at ARRL in the 1930,s, and the planetary reduction drive invented by a famous Mechanical Engineer at National Radio. I read that the Intercept antennas at Bletchley Park had an 807 power tube for Distribution Amplification, feeding the rooms of HRO's! HRO was the moniker given as the US Military purchasing - after a successful evaluation, the Govt said make as many as you can and don't stop until we tell you. HRO stood for Hellova Rush Order.. Also the coil packs could be set up for Bandspread, and responsible, along with those tubes with caps - isolating the Grid leads, allowed very wide frequency ranges AND excellent stage isolation due to no bandswitch/wiring. 73s, Hilary W4HDL
There is printed on a A4 paper something like used on a BC 221 frequency meter giving the frequency read out for the HRO. Some time ago I found the chart on the net published by a G4??? but it seems to have been taken down.
I had one of these 30yrs ago inherited from an inlaw It had bandspread coils for 80 40 20 meter bands and had been recapped however the neon regulator mod for the L.O had not been done resulting in having to re tune ssb sigs when the wife turned on the electric shower
Great stuff. I have one just the same as that and with the "dog house" PSU. I've used it with a homebrew transmitter for some CW QSOs but my HRO spends most of its time on AM Broadcast listening duty. Is there a stamped serial number plate just next to the aerial terminals on that HRO? If so you could find out its manufacture date....late 1930s perhaps. 73.
I bought a used HRO in 1957, at the age of 12. I had a newspaper route, and one of my customers sold it to me. The HRO came with 4 band plug-ins (if I remember correctly). USSR launched Sputnik on October 4, 1957, and I immediately took my HRO to art class, so we could hear Sputnik beep-beep-beep on 20 MHz as it passed overhead, every 90 minutes or so. Of course, I was given a lot of positive feedback, and the shock of USA playing 'catch-up' to the USSR, plus the money that poured into education, pushed me into electrical engineering.
I'm sorry)) I just can't believe it... I was trying to find information about radio amateurs in America who heard the First Sputnik...
My understanding was it was not difficult to hear, and I totally share your comment on Education and Engineering BOOM it forced on the US to wake up and fortunately, catch up in the Space Race. Now Elon is holding up that baton... I was 3 years old, so greatly benefited on the Science and Engineering boost. I has a Transistor and Tube radio business by 5th grade, and a mentor who was a WW2 Vet at his TV Repair shop in NNj. Read every Radio/Electronics book in Elementary school, met some Hams and got my license thru HS. Went to Bradley University with my best friend from the club, and became an EE, now still using my Ham Radio skills every day at 70, qualifying the latest 400 G Optical Networking equipment EMC, Laser and Electrical Safety certifications. I don't have an HRO, but still have my college National Radio NCX-200, NCX-3' full NCX-5 station an an NCL-2000 in restoration. 73s, Hilary W4HDL
Lovely receiver, even made Dave sound lovely,🤣👍🏻
Not noted in the Bottom View tour of this excellent Video, was the very wise modification was clearly marked as an OA2, OR VR-150. a GREAT improvement in powering the VFO and likely BFO. Without this additional regulation definitely improved this SSB demo not drifting much. Very risky leaving ANY waxies in vintage equipment at all. They absorb humidity, and the Paper dielectric has traces of Sulphur I believe, that leads to the potential damaging DC leakage. The worst case is always where a coupling cap has very high POSITIVE voltage on it, and feeds a next stage megohms input Grid at maybe -5 to -50V. This slams that tube into saturation, and may damage the plate, or if you are truly unlucky, burn out a rare Transformer's winding! These radios came out of pioneering work of George Millen and Charles Grammer at ARRL in the 1930,s, and the planetary reduction drive invented by a famous Mechanical Engineer at National Radio. I read that the Intercept antennas at Bletchley Park had an 807 power tube for Distribution Amplification, feeding the rooms of HRO's! HRO was the moniker given as the US Military purchasing - after a successful evaluation, the Govt said make as many as you can and don't stop until we tell you. HRO stood for Hellova Rush Order.. Also the coil packs could be set up for Bandspread, and responsible, along with those tubes with caps - isolating the Grid leads, allowed very wide frequency ranges AND excellent stage isolation due to no bandswitch/wiring. 73s, Hilary W4HDL
Great radio, and sounded good, back in the 60's had that 19 Set as on your bench followed by 1155, it was totaly rewired in purple wire, but worked fine, then HRO.
That was a while back 😀 enjoyable video thank you for the visit to the past.
A brilliant classic vintage receiver Justin. A friend of mine had one when I first started getting into listening to Amateur radio and I was very impressed. A must for the shack and this one looks in excellent condition. 73...David M0DAD.
What's the horizontal valve that's been added under the chassis? First receiver I had back in my youth - over 50 years ago. You know an HRO owner from the callouses that they develop on their hsnds changing the coil packs !
It's just pre-war and very many were used in listening posts feeding intercepts to Bletchley Patk.
Voltage reg valve
A very wise modification was clearly marked as an OA2, OR VR-150. a GREAT improvement in powering the VFO and likely BFO. Without this additional regulation definitely improved this SSB demo not drifting much. Very risky leaving ANY waxies in vintage equipment at all. They absorb humidity, and the Paper dielectric has traces of Sulphur I believe, that leads to the potential damaging DC leakage. The worst case is always where a coupling cap has very high POSITIVE voltage on it, and feeds a next stage megohms input Grid at maybe -5 to -50V. This slams that tube into saturation, and may damage the plate, or if you are truly unlucky, burn out a rare Transformer's winding! These radios came out of pioneering work of George Millen and Charles Grammer at ARRL in the 1930,s, and the planetary reduction drive invented by a famous Mechanical Engineer at National Radio. I read that the Intercept antennas at Bletchley Park had an 807 power tube for Distribution Amplification, feeding the rooms of HRO's! HRO was the moniker given as the US Military purchasing - after a successful evaluation, the Govt said make as many as you can and don't stop until we tell you. HRO stood for Hellova Rush Order.. Also the coil packs could be set up for Bandspread, and responsible, along with those tubes with caps - isolating the Grid leads, allowed very wide frequency ranges AND excellent stage isolation due to no bandswitch/wiring. 73s, Hilary W4HDL
love the hro.
There is printed on a A4 paper something like used on a BC 221 frequency meter giving the frequency read out for the HRO.
Some time ago I found the chart on the net published by a G4??? but it seems to have been taken down.
I had one of these 30yrs ago inherited from an inlaw
It had bandspread coils for 80 40 20 meter bands and had been recapped however the neon regulator mod for the L.O had not been done resulting in having to re tune ssb sigs when the wife turned on the electric shower
Great stuff. I have one just the same as that and with the "dog house" PSU. I've used it with a homebrew transmitter for some CW QSOs but my HRO spends most of its time on AM Broadcast listening duty. Is there a stamped serial number plate just next to the aerial terminals on that HRO? If so you could find out its manufacture date....late 1930s perhaps. 73.
Sounds really, really nice. 👍
Nice he asks "Dave" is that you? Haha Yes mister that's me !!!