What a "blast from the past"!! I was trained on this receiver at Great Lakes Naval Station, Electronics Technician "C" School in 1970. My first two duty stations were Naval Security Group Activities and utilized a great deal of these units. And they were on the destroyers I served in. The military technical manuals were very well written. If you can read and understand the theory of operation, you can fix any equipment thrown at you, which happened to me a lot in the Navy! At sea, you don't have the luxury of calling in a technician trained on a specific piece of gear!
thanks a bunch, I'm aligning one which I recently purchased... had one after college and just had to have on again because they are impressive. Well done and clear explanation. A must is the service manual which I have. I have several and there are obviously different modifications over the years which makes things a little confusing especially in the audio module. I actually prefer the (non a) version due to the smoother bandwidths via LC versus mechanical in the a version. And yes they are heavy.
I am very pleased that the video could have helped you. I know just seeing what and how others do things helps me. I use mine every time I get on 40M AM along with a 75A-4 that I picked up last summer. I have an antenna switch between for testing and comparison. They both work beautifully and the R-390 is a bit quieter. I later added the Tree Top module to this one (no longer available) but I don't think it actually helped. The Tree Top module does disable the carrier meter and large feet must be added to the rear of the receiver just in case it is set on the bottom so it won't crush the Tree Top module. I am sure you will enjoy yours. 73 WA4QGA
The R390 is a legion . We had too few of the R390 in a time when receiving a encrypted TTY signal was at times very trying due to a active sunspot period. We were often "down" during the sixtys . The cold war was no joke! A R390 was offered at a ham fest recently for $500.00 and the only reason I didnt pick it up is my back wont let me pick it up! My compliments on your camera work and i think the audio is especially clear . And uncluttered!
That is wonderful to know about TTY and sun spots during the '60's. I made a statement recently how it is interesting that sometimes we can only understand something 50 years after it has happened. You just told the same story. I am 70 and I sure agree with the weight of this magnificent instrument. 73
It is rare to find an R-390 that has not had the RF "deck" module removed at one time. Almost never is it installed correctly, A look at the underside can tell if the gear springs are loaded. Glad to see this video
Totally agree with you. It was way too intimidating to me to pull the RF deck. I spent a bunch of hours on this beauty cleaning and cleaning and...... it is beautiful now and it is my preferred receiver. I have a 75S-3 next to it but the R-390 is what I listen to. I basically only use the other receiver when I want an honest S-meter reading. Thanks for your comments.
The 20 amp fuse is for the R-391 autotune. It shares the same rear plate that the R-390 has, which is why there's a little block off plate to the right of the "REMOTE" connector, that's for the autotune.
Boy, this brings back old memories. I was stationed in what used to be the Marine Corps Supply Center, Barstow in the late '60's. I was a young corporal when they gave me 7 clapped out R-390As and told me to make 3 good ones. Managed to make 4. Did a LOT of cannibalization. The "A" was a simpler set, largely because they used 6 mechanical filters for IF selectivity. Although there are a LOT of ganged, slug tuned circuits (6 X 3 - I think - for the front end bands and 1 X 3 for the tunable IF), technically, it's a pretty simple receiver. Mechanically, however, the gear train is a bitch. The URM-25 had its own problems. The mechanical tuning drive had, if memory serves me correctly, about a 25:1 ratio. You could spend a LOT of time cranking between the upper and lower ends of each frequency band. I had just started on the variable frequency IF and I thought, "Wait a minute. This doesn't make any sense." I went back to the tool room and checked out a second URM-25. I tuned one to the lower end of each band, the other to the upper, and just changed between the two. Front end alignment went MUCH quicker. The crystal oscillator, though tedious, is relatively simple to adjust.
I just got off the air using this receiver with a gentleman back in Atlanta. The fidelity is outstanding. On any signal above the noise level, it sounds like the other party is in the room with me. It is not absolutely as sensitive as the 75S-3 or an iCom that I have but in any case, if the signal is so weak as to make it difficult to copy on the R-390, then it is also too weak to try and make a contact with the other receivers. As for the gear network - fortunately, I have not had a need to get into that and I doubt I ever will. The couplings from the tuning knob has to be adjusted and tightened when I was going thru the radio but they are spot on now. Every once in a while, I still compare it to the general purpose receiver in the iCom 736 on something like WWV and if I can hear it clearly on any receiver I have, I can also hear it just as well on the R-390. Beautiful piece of equipment. Got to be a boat-anchor lover nowadays to operate this stuff as a fellow can't jump from one band to another with the push of a button but that would take all the fun out of it for me. 73
I didn't know that but it doesn't surprise me. I agree, best receiver ever... I went to work as a NASA contractor in January 1970. It was a busy time. I stayed with them and White Sands Missile Range until 1996. Wish I could do it again.
Those are beautiful radios and you're right they aren't all that bad to work on, they're fun. You can get or used to be able to get those original line cords on ebay, I bought two of them years ago for mine. I regularly pick up European BCB stations on mine with a 160M dipole. I also have a 390A but prefer these most of them time, the sound is so much better on these.
Mine has dropped a bit in sensitivity so I probably need to go thru it very carefully and completely and not just tinker with the RF and IF tubes. Thanks for the information on the line cords.
Yes, it was daunting to try to figure out which can was to be adjusted next in the sequence by having to look back and forth in the manual and then the radio over and over. One mistake and having to start all over was not an good option. Thanks for your comments.
Hi Michael, All is well here. I have been tinkering with the R-390 lately and haven't built any amplifiers of any sort. We had a tremendous wind storm that blew down a 60 foot pine tree onto two of my cars so I have been busy with them lately. No one was hurt and both vehicles will be restored and running again soon. I did install a SSB adapter made by Tree Top out of Canada in the R-390 that I have thought of making a video of. It greatly improved SSB tuning and reception. I kind of flip back and forth between AF and RF amplifiers and I am thinking of a 4CX350 amp or maybe even a good size AM station. There seems to be very little on RUclips about AM transmitters. I still think about the promised 6AS7 amp that I made video #1 of some time back but just haven't started yet. I hope all is well with you I appreciate your email and checking in on me.
I'm glad to hear all is well. Sorry to hear about the cars though. That stinks. The SSB adapter sounds interesting. I have an old console radio from the mid-40's and it has a couple of shortwave bands that span 2.5 - 22 Mhz. AM of course. I thought it might be fun to see if I could modify it to include SSB. Carefully of course. I haven't even started restoration so it's just a thought.
Hi - how may I obtain a manual for the TS 505 ? I just ordered one of these nice remaining instruments, but no manual enclosed. Need to fine-adjust my 390A / URR. Thanks very much in advance! Cheers Volker
Here is something I found on the Internet. www.r-390a.net/Pearls/sensitivity_alignment.pdf In my case with the older R-390, about the best I have gotten on mine is being able to hear a carrier of 1 uV input. You could probably copy CW at that level but I don't think I would be able to copy voice on AM or SSB as it might not be loud enough. I also have the 51S-1 which I can easily hear 0.5 uV and amazingly the 75S-3 that I have is ever bit as good as the 51S-1 in that respect. The 51S-1 is more crisp in voice and could probably be better with noise or QRM. I have compared these to an iCom IC-736 which does not perform near as well on receive as any of these vintage vacuum tube receivers. Just my experience. Hope this helps.
What a "blast from the past"!! I was trained on this receiver at Great Lakes Naval Station, Electronics Technician "C" School in 1970. My first two duty stations were Naval Security Group Activities and utilized a great deal of these units. And they were on the destroyers I served in. The military technical manuals were very well written. If you can read and understand the theory of operation, you can fix any equipment thrown at you, which happened to me a lot in the Navy! At sea, you don't have the luxury of calling in a technician trained on a specific piece of gear!
thanks a bunch, I'm aligning one which I recently purchased... had one after college and just had to have on again because they are impressive. Well done and clear explanation. A must is the service manual which I have. I have several and there are obviously different modifications over the years which makes things a little confusing especially in the audio module. I actually prefer the (non a) version due to the smoother bandwidths via LC versus mechanical in the a version. And yes they are heavy.
I am very pleased that the video could have helped you. I know just seeing what and how others do things helps me. I use mine every time I get on 40M AM along with a 75A-4 that I picked up last summer. I have an antenna switch between for testing and comparison. They both work beautifully and the R-390 is a bit quieter. I later added the Tree Top module to this one (no longer available) but I don't think it actually helped. The Tree Top module does disable the carrier meter and large feet must be added to the rear of the receiver just in case it is set on the bottom so it won't crush the Tree Top module. I am sure you will enjoy yours. 73 WA4QGA
The R390 is a legion . We had too few of the R390 in a time when receiving a encrypted TTY signal was at times very trying due to a active sunspot period. We were often "down" during the sixtys . The cold war was no joke!
A R390 was offered at a ham fest recently for $500.00 and the only reason I didnt pick it up is my back wont let me pick it up!
My compliments on your camera work and i think the audio is especially clear . And uncluttered!
That is wonderful to know about TTY and sun spots during the '60's. I made a statement recently how it is interesting that sometimes we can only understand something 50 years after it has happened. You just told the same story. I am 70 and I sure agree with the weight of this magnificent instrument. 73
It is rare to find an R-390 that has not had the RF "deck" module removed at one time. Almost never is it installed correctly, A look at the underside can tell if the gear springs are loaded. Glad to see this video
Totally agree with you. It was way too intimidating to me to pull the RF deck. I spent a bunch of hours on this beauty cleaning and cleaning and...... it is beautiful now and it is my preferred receiver. I have a 75S-3 next to it but the R-390 is what I listen to. I basically only use the other receiver when I want an honest S-meter reading. Thanks for your comments.
Great videos. Keep them coming. Awesome workshop you have there as well.
The 20 amp fuse is for the R-391 autotune. It shares the same rear plate that the R-390 has, which is why there's a little block off plate to the right of the "REMOTE" connector, that's for the autotune.
I have an R390, Serial 495, Collins...Wow, what a receiver.
That's a gorgeous receiver. And that spectrum analyzer too. Merry Christmas. 73 NE5U Mike
Boy, this brings back old memories. I was stationed in what used to be the Marine Corps Supply Center, Barstow in the late '60's. I was a young corporal when they gave me 7 clapped out R-390As and told me to make 3 good ones. Managed to make 4. Did a LOT of cannibalization.
The "A" was a simpler set, largely because they used 6 mechanical filters for IF selectivity.
Although there are a LOT of ganged, slug tuned circuits (6 X 3 - I think - for the front end bands and 1 X 3 for the tunable IF), technically, it's a pretty simple receiver. Mechanically, however, the gear train is a bitch.
The URM-25 had its own problems. The mechanical tuning drive had, if memory serves me correctly, about a 25:1 ratio. You could spend a LOT of time cranking between the upper and lower ends of each frequency band. I had just started on the variable frequency IF and I thought, "Wait a minute. This doesn't make any sense."
I went back to the tool room and checked out a second URM-25. I tuned one to the lower end of each band, the other to the upper, and just changed between the two. Front end alignment went MUCH quicker.
The crystal oscillator, though tedious, is relatively simple to adjust.
I just got off the air using this receiver with a gentleman back in Atlanta. The fidelity is outstanding. On any signal above the noise level, it sounds like the other party is in the room with me. It is not absolutely as sensitive as the 75S-3 or an iCom that I have but in any case, if the signal is so weak as to make it difficult to copy on the R-390, then it is also too weak to try and make a contact with the other receivers.
As for the gear network - fortunately, I have not had a need to get into that and I doubt I ever will. The couplings from the tuning knob has to be adjusted and tightened when I was going thru the radio but they are spot on now. Every once in a while, I still compare it to the general purpose receiver in the iCom 736 on something like WWV and if I can hear it clearly on any receiver I have, I can also hear it just as well on the R-390. Beautiful piece of equipment. Got to be a boat-anchor lover nowadays to operate this stuff as a fellow can't jump from one band to another with the push of a button but that would take all the fun out of it for me. 73
Apollo mision was on monitor with a special version of the R-390A... Best receivers ever !
I didn't know that but it doesn't surprise me. I agree, best receiver ever... I went to work as a NASA contractor in January 1970. It was a busy time. I stayed with them and White Sands Missile Range until 1996. Wish I could do it again.
Those are beautiful radios and you're right they aren't all that bad to work on, they're fun. You can get or used to be able to get those original line cords on ebay, I bought two of them years ago for mine. I regularly pick up European BCB stations on mine with a 160M dipole. I also have a 390A but prefer these most of them time, the sound is so much better on these.
Mine has dropped a bit in sensitivity so I probably need to go thru it very carefully and completely and not just tinker with the RF and IF tubes. Thanks for the information on the line cords.
Ok i have8 of these A and non A and love your idea of marking the cans with sticker labels
Yes, it was daunting to try to figure out which can was to be adjusted next in the sequence by having to look back and forth in the manual and then the radio over and over. One mistake and having to start all over was not an good option. Thanks for your comments.
Thanks for the excellent video and all the others you have done this year. Merry Christmas 2016 to you and you family.
I love that receiver
Grande rádio
Hey David,
I was just wondering how your were doing. We haven't heard from you in a while. I hope all is well with you and yours.
Hi Michael,
All is well here. I have been tinkering with the R-390 lately and haven't built any amplifiers of any sort.
We had a tremendous wind storm that blew down a 60 foot pine tree onto two of my cars so I have been busy with them lately. No one was hurt and both vehicles will be restored and running again soon.
I did install a SSB adapter made by Tree Top out of Canada in the R-390 that I have thought of making a video of. It greatly improved SSB tuning and reception.
I kind of flip back and forth between AF and RF amplifiers and I am thinking of a 4CX350 amp or maybe even a good size AM station. There seems to be very little on RUclips about AM transmitters.
I still think about the promised 6AS7 amp that I made video #1 of some time back but just haven't started yet.
I hope all is well with you I appreciate your email and checking in on me.
I'm glad to hear all is well. Sorry to hear about the cars though. That stinks. The SSB adapter sounds interesting. I have an old console radio from the mid-40's and it has a couple of shortwave bands that span 2.5 - 22 Mhz. AM of course. I thought it might be fun to see if I could modify it to include SSB. Carefully of course. I haven't even started restoration so it's just a thought.
Hi - how may I obtain a manual for the TS 505 ? I just ordered one of these nice remaining instruments, but no manual enclosed.
Need to fine-adjust my 390A / URR.
Thanks very much in advance!
Cheers
Volker
I don't have a manual either but this is probably the best website to look at to find it. bama.edebris.com/manuals/
I found a source for the 505 manual as well as for its schematics:
www.bunkerofdoom.com/lit/ts505/ts505d.html
Cheers
Volker
Any one know the sensitivity of the 390A. ?
Here is something I found on the Internet. www.r-390a.net/Pearls/sensitivity_alignment.pdf
In my case with the older R-390, about the best I have gotten on mine is being able to hear a carrier of 1 uV input. You could probably copy CW at that level but I don't think I would be able to copy voice on AM or SSB as it might not be loud enough. I also have the 51S-1 which I can easily hear 0.5 uV and amazingly the 75S-3 that I have is ever bit as good as the 51S-1 in that respect. The 51S-1 is more crisp in voice and could probably be better with noise or QRM. I have compared these to an iCom IC-736 which does not perform near as well on receive as any of these vintage vacuum tube receivers. Just my experience. Hope this helps.
Well another video, too much moving with camera and YOU SHOW A METER AND DIDN’T SAY THE MODEL NUMBER