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I've seen a few online that are in different colours - when did you buy yours?

@@DavidMills_Physicist Hi David. Mine was in fact a Dansette GEM purchased around 1963/4. Quite a few photos online. I have no idea what ever happened to it.

Yeah, the capacitors don't seem overy critical - in my first repair video of this radio model most of the caps are cracked or otherwise duff - it still worked. It's just that I'm doing this as a repair for someone els, and I won't want it to die in service, so a cap change made sense.

@@DavidMills_Physicist cracked hunts, at low voltage, wont be a problem, and i've found smaller/lower value ones such as 0.0047 or smaller more a problem, than larger ones , in this sort of device blob a bit of superglue or wood varnish in the crack and it'll be ok,

@@andygozzo72 The first one of these I repaired the cracked caps were entirely open circuit - radio still worked after a fashion.

@@DavidMills_Physicist larger value cracked hunts , such as over 0.02 uf , i find are usually acceptable, below may be bad, i've come across caps of similar construction, except light brown colour, that had gone very leaky even at low voltage, they werent marked with any brand, though ..,

A few days after I posted this video a neighbour asked me if I wanted an old radio and handed me another one of these. I've not tested it yet.

@@DavidMills_Physicist Must be nice to have neighbours handing you vintage radios. That vernier reduction drive is a nice feature on this radio for precisely tuning in stations.

@@electronixTech They know I like old radios, I think this other oen came from a relative's attic or someting. Cause it cracked, but insode looks clean - it's not been stored in the damp.

To be exact Michael, OC44/45. 2 x OC81 1 x OC81D if I recall. Was a very long time ago.

Congratulations on the repair, I found tweaking the IF for max signal on a weak station did improve sensitvity. If you have a sig gen you can do a proper alignment, but it's so wide, you really don't need anything fancy.

I thought about that but didn't in the end (I've never done an IF alignment before although I know the theory!). I was just repairing/cleaning it up for a friend for sentimental reasons - it was her father's radio back in the 1960s. I have to say that it was much easier to work on than the valve sets I've done before. I put the new caps in the same locations as the originals, so it doesn't look so "empty" inside.@@DavidMills_Physicist

@@gordonlyon2351 I've just been given another one to fix. The capacitors look a bit better in this one, but the case is trash. Might end up making one good one from the two.

@@DavidMills_Physicist I was lucky in that the case on mine was in good nick. It only needed a clean. There's a small crack on the bottom but I just put a bit of superglue on it and it's fine. I had to be a bit experimental with the values of some of the caps but it seems to have worked out OK.

@@gordonlyon2351 i have a 222, rough case but working nicely, virgin unrecapped as they didnt need changing, hunts caps used in low voltage/low impedance circuits like a transistor radio do not need replacing on sight, even if cracked, only if theyre actually bad, such as gone open (any dc leakage on low dc, which will be minimal or non existent, is irrelevant in low impedance circuits)

I was lucky, I didn't have to remove those. The trick for a stuck tuning dial is two fold some think cotton material around and under the dial then pull up, it spreads the load and prevents the dial cracking.

Same

Hi Josh, I'll check. I'm pretty sure I still have the original CD for my 800 series camera around.

@@DavidMills_Physicist Thanks man! Excuse my ignorance, but I’m assuming you’ll be able to just send the Program over without the CD once you’ve got in on your computer? I was just introduced to LabVIEW recently and my knowledge of it is very limited. I’m planning to use this CCD experience to learn a thing or two about talking to devices.

@@Sardinie14 I've put a copy of the software that runs with the 800 series camera here: www.dropbox.com/sh/5ro3idsvefvpgkk/AAB6Ue3tFy7FELTJw5JAiXD3a?dl=0 Let me know when you've got it and I can remove the link. The Labview is compiled (I think, I don;t really know labview) so I'm not sure if this will be much use to you. Good luck with your project.

​ ​@@DavidMills_Physicist I've got it. I'm not sure if it will be of much use either but it is a start! I'm a physics student currently being introduced to LabVIEW for my research. But, I also love astrophotography. I saw mike's video about these cameras and figured I would give it a go to try and learn a thing or two. If it winds up as an expensive paperweight. So be it haha. Thanks again man, really appreciate it. Cheers - Josh

I'm sorry - I don;t have the circuit diagram to hand, it was a quick experiment. The transistors I used were 2n3904, so you can probably reverse engineer the circuit if you pause the video when the board is shown. Good luck.

Thanks - I've been enjoying fixing a few old radios during the various lockdowns. I've got another on the bench now, I should make a video for that one - it's missing just about everything.

Thank you. I am planning to make more videos in this series, I just need to find some time...

I can, and have done many times, but now I have the tools why makes things harder than they have to be?

@@DavidMills_Physicist Then people can not learn how to do it unless they spend $$$. It just turns off the youngsters who want to learn and can not spend $$$.

Thank you! Good luck with your studies.

It's a bit difficult to go into in a comment, but basically you're looking to see if the base is biased (has a voltage around half the supply voltage on it) and that there is voltage on the collector. Remember, most if not all germanium transistors you'll come across are PNP, so the emitter will be positive and the base & collector will be negative.

And you nice comment, I'm just dealing with some other issues moment and plan to get the next couple of videos out in a few days time