Hi Ray, I hope you are well. I caught COVID in 2022 and am now on oxygen but coping ok. Since feeling a bit better I've got my radios out again and although still using the flower pot antenna I thought I would invest in a GA-800 active loop. It works very well on shortwave but though it states up 159Mhz I can't a dickie bird (good umpire he was) on air band. I've tried my other radios (3 in all) and still nothing and they all work on the flower pot. I have searched and searched the net but can't find a thing about them. I have a feeling though they state they go to 159Mhz its all FM after 88Mhz and doesn't switch to AM for the air band. I was hoping you might be able to shed some light on this please.
Hi Martin, sorry to hear about your health. My Tecsun switches to AM when on the airband and it doesn't go up to 159MHz. All I can think is they must have changed the spec. I'm afraid I can't be of any help but, if I discover anything, I'll let you know. Cheers, Ray.
Hello again Ray. Thank you for your answer. Perhaps I didn’t make my self clear. My radios are fine it’s the GA-800 antenna that’s the problem. If I plug it into any of my radios it won’t hear any air band even though the spec says up to 159Mhz. The flower pot antenna and my discone work ok. I bought the GA 800 because it’s portable.
Nice RX but not very sensitive like all aircraft RX of that era. At that time HF was overcrowded so sensitive RX could produce dozens signals on single freqeuncy! All armies were in the air on CW, Air Force, Navy, PTTs, and many other organisations, all was on CW.
I recently got my hands on a Tandberg 3600XD and replaced the brake pads much like you did along with replacing all rubber parts akin to your solutions. The only issue remaining is a fuse that keeps burning out due to shorting somewhere, so I’ll have to look into where the electronics are shorting out. Really great video, really helped me to get going with fixing the mechanical bits on the deck
I'm glad you found the video useful. I still haven't finished working on my Tandberg. The rewind doesn't work properly but I will get there, in the end. Cheers, Ray.
I have a 12m mast with a 1/4 wave centre loaded virtical for 80m to get on 160m i add a loading coil at the Base i have worked dx on 160m only 100w here my garden is only 10 x 20 ft and i dont need a atu chris G0WFH
Ray your explanation is a joy to listen to. I loved your quote "everything inside the coax is its own private world" To many people on RU-vid think they know but in all reality they know foxtrot Alfa 😂and give newcomers bad advice 73
Here are some LW stations that I heard just recently via a UK online SDR: 153 Antena Satelor Brasov ROM 171 Medi 1 Nador MRC 198 BBC R4 Droitwich G (BBC WS) 225 Polskie R. Solec-Kujawski POL 252 R.Algerienne 3 Tipaza ALG
I’m in New Zealand work and I scrap yard and someone dumped a couple of Old NZ postal service radios So I cracked them open to see what frequency chips they had and they were 25 MHz. I tried to get one to fire up. It did go but she was in pretty bad shape but who knows? I might be able to resurrect it. in the past I was a bit of an avid CB fan New Zealand back in the day ran 26 MHz. My father was an Old School ham radio operator passed away back in the mid 90s. He taught me quite a bit but I really miss those days operating 10 -12 and 11 meter bands with him on the side.
Hi Gordon, it's good to hear from you. That's interesting about the postal service radios. Hopefully, you can get them going. OK on the CB bands, great stuff! Cheers, Ray.
Ray, during your searches for info on these HRO sets, did you come across this RU-vid Sute..."AWA Communication Technology" for there is a video on this site titled "The History and Identification of National HRO Receivers". This site gives details as to where you may find your receivers serial number. This serial number can then be used to identify the set model and year built. This video is now a year old so will be somewhere down the play list.
Ray, I have a National NC-2D that has the same three position switch you removed. Position 1 allows the receiver to heat up so there is no drift i.e. reception is cut off. Position 2 is "manual" with no AGC. Position 3 is AGC. A friend of mine sent the radio to me as we both worked in SIGINT in the 80's. He found it at a radio convention, abused and left for dead. I refurbished it. It's a boat anchor! I named her "Natalie" for National Radio. She was made in 1947. Also, really enjoy your videos. You remind me of the gentlemen who introduced me to radio when I was 16. Keep making videos, Old Man. Cheers -- Buzz
Hi Buzz, my switch wasn't wired that way but tjhat's interesting. Natalie... I like that. I'll have to think of a name for my HRO. More videos on the way! Cheers, Ray.
Well done on finding these elusive articles Ray. You are like a Super-sleuth tracking down this information to allow you to make progress. Fascinating series. Thank you.
Is the Navy coil pack the one you had to drill a hole in to get the receiver to accept it? Perhaps that's why there was no hole, as the IF was different. This receiver is a fun journey, as long as it doesn't make you mad. I'll be here for any amount of episodes. Cheers, Ray.
First off I think you saved me a RF burn. Second question can you be too high off the ground horizontally to break the circuit? I don’t want to use a tuner, is there a position that would raise the SWR in relation to the circuit? Lastly that you.. brilliant lesson. VE3WLX
Hi, great to hear from you. That's a qood question. Too high about the ground... yes, I suppose an end-fed too high up would break the circuit. To be honest, I'm not sure. Cheers, Ray.
Fantastic, Ray. Surprised that SSB resolution works so well, as I thought these old radios were for just CW and AM. Keep up the good work with getting the radio in top working condition.
Ray, I believe people "gronch" the adjustable components because they're desperate to learn how the unit works. It's also a result of far too few mentors available to satisfy the next generation. I too did a few gronches as a lad and worked my way up to 50Kw with great success as a broadcast engineer. Your channel is very important as it teaches and mentors that new breed that wants to walk in your footsteps. Be patient with them. Show them the correct way and the proper tools to use. That's what I try to do now with my peeps. PS. I wish I had an answer to the crystal question. Only thing I can come up with it that it's lightly loaded by capacitance coupling and without the spacers we have an impedance mismatch (heavy loading) on the crystal and thus a low Q. That's my best guess. 73 OM Looking forward to the next video.
Yes, I agree that people might want to learn how the unit works. As you say, there are far too few mentors around these days. I shall be patient. That's a good point about the crystal and lightly loaded by capacitance coupling. More videos coming soon! Cheers, Ray.
Hi Ray, Great video, many thanks. Perhaps during a future video or in one of the weekly videos you could explain why the US navy needed to change the IF to 175kHz in order to receive 400-500kHz. I gather there is some problem with receiving broadcasts at the same frequency as the IF.
@@g4nsj Thanks. I guess on thinking about this a bit more, if the incoming frequency and IF are too close there will be a tendency for them to lock together in the mixer resulting in dead zones in the receive band.
I had to laugh when you said "Graunch". That was a favourite saying of my dad when he heard someone doing a bad gear change. Turns out that it was a popular saying amongst motorcyclists too in the mid 70s as I remember.
Lovely bit of kit ray.....not seen one of your vids for a while.....I worked NZ for the first time this morning with the help of my doublet antenna..... One of your vids introduced me to the fantastic Doublet quite some years ago. Thanks so much for your videos Ray.
@@g4nsj Yes, I know, it is a very common mistake also because it is used as an antenna but it is a probe. A probe takes signal from the field without perturb it. This is also represented in the depiction of the electric field lines in the link you indicated and the very very high input impedance of the first amplification stage is necessary just because it is a probe, not an antenna. The noise level I see on your rx is too high for a villa: in my case, a condominium in a large city, it is lower. At the lowest frequencies what matters is the signal / noise ratio and not the signal level (they all necessarily have to be very high because the natural noise at those frequencies is high). So try to power also your radio with batteries and cut off electricity to the whole house: this way you will know whether to start hunting for a source of noise in your home. The miniwhip "probe" (probe 😉) can also help you in that search. Noise can also increase due to the presence of strong signals at the miniwhip input: on the original project the second transistor was an obsolete and difficult to find type (2N5109 do not buy it in China!) but necessary for the miniwhip to have the great dynamics that is needed: check the one you bought and, if you find a 2N5109, put an alcohol drop on it to know if it is genuine. If you think that there could be strong signals from FM or TV broadcast, you can add a VK100 or VK200 at the amplifier input. Finally, to avoid that the cable collects noise you can use two small transformers, suitable for the signals to be transferred, placed at the ends of a balanced line and solving the problem of the power supply separately or you can attenuate what the braid collects preparing two large chokes with many many tiny coax coils on a toroid with very high permeability for those frequencies. Good DX.
National did sell a noise limiter as a add on and some HRO where sold as factory standard fitting. hence maybe the hole on the left side of the face plate and this where it would be fitted.
Ray, I commented last video about a move here in the US to eliminate AM radios in new cars. I did just a little internet research about this. The car manufacturers evidently are having trouble with interference from the electric motors on EVs. There is so much interference from all of the cheap switching power supplies in our home devices it is hard to get a clean signal. My new washing machine produces bad interference on my AM radio in my shop. When my wife heats water in her Keurig coffee maker, it completely wipes out my AM radio while boiling the water. I am sure big money of the car industry will win out. Take care, I enjoy your channel, I no longer do any electronic repair retired now for 11 years, but I understand everything you are talking about. I spent 42 years working in industrial controls, land based microwave and commercial two-way radio systems.
Yes, I remember you comment about AM car radios. Interesting about the EVs. Crikey! Even more interference! I use a miniwhip active antenna for medium wave DXing, which is pretty good. Enjoy your retirement! Cheers, Ray.
Don’t ever worry about thinking that you’re explaining too much you do a brilliant job and even non-registered blind. I know exactly what you’re talking about. I love my vintage radios but I also love my transistor radios so don’t worry about what other people think what you think is right for the video is right for you, honest I wish I had your skills
The Germans in WW2 copy the HRO They purchased the dial and tuning caps under the noses of National radio through Portugal. However they used German metal tubes
A few years ago I found a web page for the HRO giving a list of frequency's and dial setting versa frequency and printed it of on to A4 paper. covering most of the coil sets If you have seen a BC221 booklet its the very same idea. The site I think has been deleted.
"Peyton Place". 🤣😂🤣 Oh, my Days, Ray. Well, another informative video, thank you, you make them Ray and we'll watch them. Take care and see you for the next one.
Strange how the receiver cuts out at a particular frequency when using that coil pack. Any clue in the fact that you get that static click when the receiver cuts out, Ray "?".
Another fascinating video Ray. I so much enjoy these update videos about the HRO. It was such a pleasure to talk to you on top-band this afternoon and hear myself on your HRO while we had a duplex conversation, with you on 2 meters.
Thanks, Roy. Crossband GB3RW to 160metres... People don't seem to do that sort of thing these days. It was a great QSO. We're keeping the hobby alive! I've just heard Mid Downs radio on 1350KHz from the Princess Royal Hospital, Haywards Heath. Cheers, Ray.
