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Vintage Radio (domestic) Domestic vintage radio (wireless) receivers only. |
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31st Dec 2016, 1:46 pm | #301 |
Heptode
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Re: My first valve radio project - Philips 462A
Well done Nicola, wow Lawrence what an expirence it's been, Nicola, there are still plenty of stations to pick up on MW and there's still RTE Radio 1 and Radio 4 on LW plus a few French stations too. Why not have a go. Something like a Bush DAC90A you would sail through that with ease.
Paul. |
31st Dec 2016, 1:57 pm | #302 |
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Re: My first valve radio project - Philips 462A
You could try a 10nF for C24 but as it is a tone corrector using a 10x value will make the audio sound much more muffled.
There are still a lot of MW stations about, local radio stations and music type stations, it depends on what you listen to. Mike |
31st Dec 2016, 5:08 pm | #303 | ||
Heptode
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Re: My first valve radio project - Philips 462A
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31st Dec 2016, 7:37 pm | #304 |
Retired Dormant Member
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Location: Loughborough, Leicestershire, UK.
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Re: My first valve radio project - Philips 462A
I was just joking about the telling off Thanks for the advice on capacitance. I'll fit a 1nF in that case. I may well try out the AM receiver just to see if it works
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31st Dec 2016, 9:48 pm | #305 |
Dekatron
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Re: My first valve radio project - Philips 462A
Make sure the on/off switch contacts are not dirty causing high resistance.
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31st Dec 2016, 11:07 pm | #306 |
Dekatron
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Re: My first valve radio project - Philips 462A
I am afraid I was a bit late in posting,as what I answered to is long gone.
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5th Jan 2017, 8:48 pm | #307 |
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Re: My first valve radio project - Philips 462A
I've replaced the two resistors and tidied things up and the set is working nicely. However, with bluetooth module installed I have an annoying volume-dependent buzzing through the speakers..
This is what I've done: The audio input from bluetooth to the set has been wired in with a 47K resistor in series before going into the gram pick up socket. The bluetooth module is the kind that plugs into a USB port for its power. So I have opened up one of those 240V wall plugs that have a USB port and wired it directly into the sets on/off switch. So its only on when the set is on. The last time I did this in a radiogram I had an separate on/off switch for the blue tooth power so it could be switch off when I was playing gram or radio. When I switched the bluetooth off (but radiogram still on) I got loud buzzing because the bluetooth went very high impedance when off. This was solved by adding a 47k resistor across each channel input to ground. This time, by wiring into the sets on/off I have avoided the high impedance issue but this time get a buzz when the bluetooth is on. Could this be a proximity thing? I have the 240V-5V plug very close to the mains transformer in the set. Any ideas on what to try to stop the buzzing? |
5th Jan 2017, 9:34 pm | #308 |
Dekatron
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Re: My first valve radio project - Philips 462A
I think the hum is being picked up on the (possibly unshielded) audio cable from the Bluetooth receiver to the PU sockets. This is upstream of the radio's volume control, so will be affected by that.
If so, it could be mitigated by careful routing of the audio cable away from the mains transformer, and / or by using shielded cable for this connection.
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5th Jan 2017, 9:37 pm | #309 |
Dekatron
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Re: My first valve radio project - Philips 462A
I know zilch about Bluetooth but that unit looks too close to the mains transformer.
Lawrence. |
5th Jan 2017, 11:59 pm | #310 |
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Re: My first valve radio project - Philips 462A
Bluetooth is digital. The module could simply be radiating RF c**p into the set.......
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6th Jan 2017, 4:24 pm | #311 |
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Re: My first valve radio project - Philips 462A
Hi, I would suggest that you check to see that the 47K resistor is wired into the "live" or "grid" connection to your pick-up socket. I.E. the socket which hums if you touch it with a screwdriver when on gram. the other socket should be ground for audio, and should have a direct connection to the blue tooth unit. Tony
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7th Jan 2017, 8:36 pm | #312 |
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Re: My first valve radio project - Philips 462A
FINAL UPDATE: The buzzing was stopped by moving the mains cable over to the side underneath the machine. It was interacting with one of the components but I don't know which one. The proximity of the bluetooth receiver to the transformer did not appear to be an issue.
So, here it is my Philips 462A in all its glory. Playing clear and loud and looking absolutely fantastic!! I love it and my friend saw it today and was knocked out by it and now wants one herself! Thanks for all the help, especially Lawrence of course. I have learnt so much on this journey and am dying to start on my next radio set (I have already got one in my sights but hopefully it will be a little more straight forward next time!). The set plays digital music now rather than its original AM frequencies so its not a 100% restoration but it will now get used again rather than sitting covered in dust in someones attic. I decided to remove the AM frequency receiving components in the end so they can be used in a restoration by someone else (on sale in the offered section here if anyone's interested). Thanks again...until the next time.... Nicola |
7th Jan 2017, 8:51 pm | #313 |
Dekatron
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Re: My first valve radio project - Philips 462A
I'm glad your project turned out as you wanted it too, it's polished up good as well, need another one now for stereo...
Keep at it. Lawrence. |
8th Jan 2017, 4:21 pm | #314 | |
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Re: My first valve radio project - Philips 462A
Quote:
PS. It does look good, though. |
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22nd Jan 2017, 3:00 pm | #315 |
Dekatron
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Re: My first valve radio project - Philips 462A
As this radio is now on eBay, the Forum has no further interest in it.
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