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-   -   Help to identify old Philips valve radio. BIF 571A. (https://www.vintage-radio.net/forum/showthread.php?t=157354)

stofbj1 16th Jun 2019 11:16 pm

Help to identify old Philips valve radio. BIF 571A.
 
3 Attachment(s)
Hi,
I am no expert on valves, they were way before my time.
Hope someone can help to identify an old Philips valve radio, the only number on the back is 2H61644. I am looking for a schematic diagram for this. The radio works but the volume is very, very low. I checked the main filter electrolytic cap 50+50uf and its reading 49 + 41.4 which is not bad, another 5mf is reading 4.9uf, and one 100uf 12.5V negative end going to chassis and positive to a valve, this is reading high at 162uf. Another 2200pF is reading 4630pF so well out of spec. The reason I need the schematic is because there is another black beauty and I can not make out the reading on it. All the valves seem to light OK.
I have already cleaned out the variable tuning capacitor metal plates and the switch contacts. Any help would be appreciated, the stations it does pick up are clear, no hum just the volume issue. One one off knob is missing in the picture. I will take some voltage readings on the main filter cap tomorrow.

Thanks in advance.

Mr 1936 17th Jun 2019 8:57 am

Re: Help to identify old Philips valve radio
 
Hi. I can't identify the set, but from the appearance it would seem to date from about 1955. There may be a date stamp on the main smoother. Later sets went in for concentric knobs and "piano key" switches. Remember that the tolerance on capacitors may only have been +/- 20% when new, with electrolytics sometimes even wider, so capacitance variation may not indicate anything amiss. More important is leakage, which an ordinary tester may not be good at measuring.
Does it have VHF / FM ?. If Medium/Long wave and FM stations are equally quiet it would point to an issue with the common audio sections rather than the RF or IF ones.

paulsherwin 17th Jun 2019 9:20 am

Re: Help to identify old Philips valve radio
 
It's probably a Philips Ireland model, though the unusual model number doesn't correspond to this (there would normally be an 'IF' in there somewhere, for Irish Freestate). It doesn't appear to have VHF, which is to be expected as the Republic didn't start FM until later, though the BBC would have been available in some places from NI. I agree it appears to be from the second half of the 50s, after Philips made the switch from B8A to B9A valves.

Station X 17th Jun 2019 9:36 am

Re: Help to identify old Philips valve radio
 
What's the valve line up?

simpsons 17th Jun 2019 10:02 am

Re: Help to identify old Philips valve radio
 
I might be mistaken but isn't there an internal FM aerial connected to the top of the chassis together with a couple of extra valves - FM RF and Mixer with its tuning capacitor or variable inductance driven by a circular thingy from the tuning drive ?

Identifying the valve line up will tell you all and that there will be many similar circuits to choose from to help you narrow down the fault.

paulsherwin 17th Jun 2019 10:05 am

Re: Help to identify old Philips valve radio
 
It isn't clear from the photo if the bottom of the tuning scale is marked for SW or VHF. If VHF, it may be that the model was introduced for the launch of FM in the Republic.

stofbj1 17th Jun 2019 10:08 am

Re: Help to identify old Philips valve radio
 
Hi,
I think I found the issue, from the centre tap on the on / off volume there is a white resistor going to the first valve, this is not reading anything, there are no markings on the resistor, just white, does anyone have any idea what value this should be? also what wattage it should be?

Station X 17th Jun 2019 10:11 am

Re: Help to identify old Philips valve radio
 
In that position it's more likely to be a capacitor. What type is the "first" valve and which pin does the component connect to?

stofbj1 17th Jun 2019 10:36 am

Re: Help to identify old Philips valve radio
 
3 Attachment(s)
Hi,
Thanks everyone for your help so far.

Yes this set has VHF on the very bottom of the display, I can pick up FM but volume is very low, I am no expert on valves, All I know they are all glowing :) they were well before my time, but am willing to learn. I have no valve test equipment.

The reason I though it is a resistor is because I see another one exactly the same and its reading 10K ohms.

Here are some pictures of it, for the eagle eyed I have it disconnected at one end, it goes to the centre of the first valve, I took the valve out for inspection and there are no marking on it, cleaned the pins while I had it out.

Maarten 17th Jun 2019 10:50 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by paulsherwin (Post 1153284)
It's probably a Philips Ireland model, though the unusual model number doesn't correspond to this (there would normally be an 'IF' in there somewhere, for Irish Freestate).

Must have missed that, or do you mean the part number of the backplate? Strangely, starting with 2H, that seems to the best of my knowledge a Dutch temporary part number. Such numbers were used in prototypes and in case production was rushed.

One coil has a normal Dutch number (A3), the other coil and transformer have British numbers (MK).

The date codes 20, 23 and 26 respectively, don't really make sense unless the first digit indicates the year (on the continent it's the last digit). Possibly 1952 in that case.

@stofbj1: could you take a picture showing the remains of the type label on the chassis?

stofbj1 17th Jun 2019 10:55 am

Re: Help to identify old Philips valve radio
 
So just need to identify the object on the 3rd picture, I presume this is a resistor? But what value?

Station X 17th Jun 2019 10:56 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by stofbj1 (Post 1153310)
Hi,
Here are some pictures of it, for the eagle eyed I have it disconnected at one end, it goes to the center of the first valve, I took the valve out for inspection and there are no marking on it, cleaned the pins while I had it out.

By "centre" do you mean the tubular structure in the centre of the valve holder? This is normally connected to chassis ground.

Can you tell us what other valves are fitted? Is there a valve placement diagram on the back cover or perhaps on a label somewhere?

EDIT. When looking from UNDER the chassis valve pins number clockwise from the gap in the pins or the spigot.

paulsherwin 17th Jun 2019 10:56 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by Maarten (Post 1153312)
Quote:

Originally Posted by paulsherwin (Post 1153284)
It's probably a Philips Ireland model, though the unusual model number doesn't correspond to this (there would normally be an 'IF' in there somewhere, for Irish Freestate).

Must have missed that, or do you mean the part number of the backplate? Strangely, starting with 2H, that seems to the best of my knowledge a Dutch temporary part number. Such numbers were used in prototypes and in case production was rushed.

One coil has a normal Dutch number (A3), the other coil and transformer have British numbers (MK).

The date codes 20, 23 and 26 respectively, don't really make sense unless the first digit indicates the year (on the continent it's the last digit). Possibly 1952 in that case.

I meant the only number visible on the cardboard back panel.

The Irish operation was quite small by Philips standards, and though they did build a complete range of locally designed models, the components were all sourced from different Philips divisions.

I guess this model could have been an Irish pre production prototype in preparation for the launch of VHF/FM. RTE only operated a single radio station until well into the 60s, but I can't find info about the dates.

stofbj1 17th Jun 2019 11:03 am

Re: Help to identify old Philips valve radio
 
5 Attachment(s)
Ah found a damaged sticker on the chassis, with some numbers on the chassis when I removed the already damaged sticker,

ms660 17th Jun 2019 11:09 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by stofbj1 (Post 1153315)
So just need to identify the object on the 3rd picture, I presume this is a resistor? But what value?

The object the pen is pointing to looks like a tubular ceramic capacitor to me, if there are no markings on it then it's anyone's guess what its value is without a schematic or knowing it's position in circuit.

Testing capacitors in circuit can be a hit and miss game if you are not experienced enough to know what's what due to parallel resistance paths etc.

Lawrence.

paulsherwin 17th Jun 2019 11:10 am

Re: Help to identify old Philips valve radio
 
Those are just part numbers I think.

Paul JD 17th Jun 2019 11:13 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by stofbj1 (Post 1153315)
So just need to identify the object on the 3rd picture, I presume this is a resistor? But what value?

The white component with the pen pointing at it is a capacitor (ceramic "dog bone" type). They usually have the value marked on them or colour coded dots.

Edit: crossed with previous post by ms660!

stofbj1 17th Jun 2019 11:15 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by Station X (Post 1153317)
By "centre" do you mean the tubular structure in the centre of the valve holder? This is normally connected to chassis ground.

Can you tell us what other valves are fitted? Is there a valve placement diagram on the back cover or perhaps on a label somewhere?

EDIT. When looking from UNDER the chassis valve pins number clockwise from the gap in the pins or the spigot.

Sorry made a mistake, was just confirming with a continuity tester and yes the centre of the valve goes to ground, (did not even know that) but I was looking at the wrong resistor to the right, the one going from the centre tap from the volume goes to one of the pins on the unnamed valve, The resistor is not reading anything, since I am having volume issues and this comes from the volume pot, I presume this is the issue, but any idea what the value could be?

stofbj1 17th Jun 2019 11:21 am

Re: Help to identify old Philips valve radio
 
Quote:

Originally Posted by ms660 (Post 1153323)
The object the pen is pointing to looks like a tubular ceramic capacitor to me, if there are no markings on it then it's anyone's guess what its value is without a schematic or knowing it's position in circuit.

Testing capacitors in circuit can be a hit and miss game if you are not experienced enough to know what's what due to parallel resistance paths etc.

Yes that is way I have is disconnected, I just found a marking on it on the bottom 4k7 is this a capacitor then?

paulsherwin 17th Jun 2019 11:21 am

Re: Help to identify old Philips valve radio
 
What aerial are you using?


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