I already have the service instructions and associated data, it's just the owners manual that I want please. I'm in the UK. When the Post Office folded up the manual for the B he sent, he sent another no problem. Well made and look a lot like originals. Don't know if he ships to UK but you can always email him and find out. E T Extra class ham on the radio and in real life, nyuk nyuk nyuk. Just one thing, the model type is slightly different, so I hope this does not impact on the user manual too much.
Can anyone elaborate please? Mine is a , which has a crystal controlled weather band.. Later models, perhaps yours, tunes the entire weather frequency band. I don't have one to compare That would be a major operational difference. When I was looking for an H manual the seller sent me scans of certain pages to see if they matched up with my radio, since there were so many chassis variations. Turned out his manual did not match my chassis in that case. So he might do that for you, too.
I notice the picture on the front of the D manual shows the inside of the open front cover to be black enamel, where on the Royal like mine , it shows the open inside front cover to be brushed stainless steel. That might be a clue. Note that he also sells the manuals without the schematic for a few bucks less. So even if there were differences in the schematic, but no differences operationally, you could just get the manual.
I did some signal tracing and soon discovered that one of the transistors in the push-pull output section was bad. These are matched pairs and replacing them with anything other than a matched pair will degrade audio performance. Gone was that ripping distortion as I increased the volume. Confident that the radio was essentially working properly I turned my attention to finer details. While it initially looked fine I could now see that there was a slight dent in it…the sort of thing you had to get at just the right angle to see.
It is held in place by the kind of metal tab which can sometimes survive being straightened and re-bent once before they snap off. Straighten them out to pull the metal grill forward and off. I tried to press it outward from the inside, but it returned to its creased shape as soon as I released pressure.
I ended up laying the grill flat on the workbench covered with a few layers of cloth and used a small wooden roller from the inside. That reduced the crease to the point where it as now extremely hard to see under any conditions. The other thing that bothered me was the dial glass…it was cloudy and it detracted from that fresh, crisp look the dial had when it was out of the case.
I was not able to reduce this haziness using the Novus Plastic Polishes, which usually work very well for this. I went to the auto parts store and bought a product used to clean the rear window of convertibles…it was near miraculous. It left the dial clear and shiny…absolutely amazing! Luckily there was no such issue here. Many people avoid alignment, but in actuality it is an easy process once you understand it and is the natural final step to any major repair, and is generally necessary on older radios to get everything back to original specs.
But sometimes on older radios, due to aging of components, alignment does not come out quite as perfectly as one would like unless you learn how to fudge the rules just a bit. In the case of this particular radio the worst problem I saw was very bad AM dial calibration, although reception seemed good.
AM is the first band to be aligned in the sequence, and that allowed me to experiment a bit before I proceeded to the shortwave adjustments. The problem I was having was that, no matter how I aligned the I could not get the dial tracking to be right. If it was correct at one part of the dial it was off at another by an unacceptable amount, 30 to 40 KHz. I discovered that when I started out with the tuning gang fully open clockwise and set the frequency for KHz as outlined, when I then turned the dial down to the radio was actually tuned to about In other words, as I tuned down from toward on the dial the actual tuned frequency was only beginning to decrease and at too slow a rate.
What would cause this? My best intuition tells me that some component values have subtly changed. Attempting to measure these components would be a lesson in futility as most would have to be removed from the circuit to test properly.
The most obvious would be to simply set the dial to and align to that frequency, but I avoid that method except as a last resort. This unit is supposed to top out at KHz when the condenser is fully opened and I wanted to start with that specification satisfied. One way to deal with this symptom is to adjust the position of the dial pointer on the string. This is itself a calibration point in some, but not most, alignment instructions. It was more common in earlier days and now seems to be assumed rather than stated.
Some radios have actual calibration marks…say at the bottom end of the dial, where the pointer should rest when turned all the way in that direction. My dial pointer was a bit to the left of what looked like the optimum position, so I loosened it on its string carefully and slid it a bit to the right until it seemed to span the dial scale properly.
Now when I set the frequency to and aligned the radio with the dial all the way to the right, then tuned the dial down to , the radio was very tuned very closely to Once I realized the dial was in the wrong spot on its string it all fell into place…it is likely this sample was always this way from the day it was new. Better AM radios have a so-called padder adjustment, generally performed at KHz.
When you are told to make a rocking adjustment at KHz the procedure is this. Tune your RF generator to KHz and tune in the signal on the radio.
Hopefully the dial will indicate exactly KHz, but for now just tune for maximum signal. Then align the adjustment point for maximum signal strength. Now, keeping the generator at KHz, tune the radio higher in frequency just a bit, then re-peak your alignment point and note whether the signal is stronger or weaker than before. If it is stronger, turn the dial further in the same direction and peak the alignment point again. Keep turning upward and re-peaking until the result is a weaker signal, then turn the dial in the opposite direction and repeak.
You are looking for whatever point on the dial yields the strongest signal after the alignment point is peaked. This is the proper adjustment, even if the dial does not indicate exactly KHz. Generally the error will be subtle, and getting the maximum performance is the most important goal.
Many technicians unfortunately simply put the dial at and peak the adjustment for maximum, leaving a severely desensitized radio. Alignment continued through all the bands without any further problems, and all the bands seemed to exhibit similar sensitivity and selectivity.
I was confident it was working properly on all bands. This is the easiest time to do it and when the set is finally put back together your radio will look dramatically fresher and neater than when you received it. Other than removing the dent from the grille and getting rid of the haze on the clear plastic dial cover as I discussed earlier, the only other cosmetic work needed was a general cleaning of the knobs and case exterior.
Nothing special here, and typical of many old radios this one had a few paint specs here and there. I finished up with Novus Plastic Polish 2 and 1 and was rewarded with a gleaming looking case…really about as nice as something this old can be unless it was sealed away and never used.
I also wanted to replace the lamps…two of the three were working two for the dial scale, and the third for the flip-up chart light. Unfortunately the lamps I bought were pre-focused and did not illuminate the dial scale evenly. I ended up ordering the correct lamps from an online source…they were inexpensive and arrived within less than a week. It is possible to change the dial lamps by simply removing the back cover, but it is easier when the chassis is out of the cabinet.
I found the two drum-mounted lamp sockets were a bit dodgy…I cleaned them as well as I could by hand then applied a light dab of contact cleaner before I put the new lamps in place. As I put the back cover back on I felt I now knew this radio inside and out — that always seems to add to my appreciation and enjoyment of any electronic item.
I did some informal reception tests against my other portable AM and Shortwave radios of various vintages and found the DY performed very well.
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