Philips 2514

[CambridgeWorks]

This is quite different ftom other projects on here.
Full credit for what you have achieved using modern, but obtainable alternatives.
At least you can enjoy listening to it, long may that continue.
The fact that your modern parts can be replaced with original parts and still work is quite an achievement in your design work.
Rob
Rob

[boiss]

Originally Posted by Rich Woods

I must admit the definition here of “non modification” is making me smile. Personally I would have converted to take more readily available contemporary valves as it would definitely have a more authentic feel to the restoration. Nevertheless an interesting project. Each to their own I guess.

Which Contemporary valves? ( to replace 509K,(K is important) B442 and E415)
Adding the 39K resistor and decoupling cap in series with the regen cct will have minimum effect, ie. the radio will work perfectly by just inserting the 3 correct unobtainable valves, after all the Mosfets and circuits are on sockets that plug into the bases with side and top connections. . Rs and Cs were replaced but they are not visible, and apart from the Main smoothing caps in the big can all values are the original ones. Conversion to more modern valves was a big NO.
"Non modification" I took the easiest route with the minimum change to the basic radio, Anyone with minimum knowledge could undo my little mod and put in a few hundred euros of valves in 5 minutes and be listening.
All the main WW resistors are still in place and only a few high value Carbon? resistors were found to be defective and replaced with hi stab metal oxide resistors (Sorry). Wiring to side connectors (PVC not DSC) Sorry again, and top cap were replaced using original solder tags.
This model radio is a real pain to work on, there are a few faults that can occurr and cause a lot of work. A S/C on the HT causes the Bias pot or its tail resistor to burn out if you are lucky. This means removing the mains tranny and some very careful diss/re-assy of the interior side panel. Re-assy of the box with the interstage and O/P transformer is interesting too!
Anyway enough, If some purist wants to "Give" me the valves I will gladly undo my cct mod and fit the valves. While I'm waiting I will use it as it is now.
Actually that is a lie because I have to make and fit a bottom panel and with a new Philips Made in Holland plaque duly punched.

[Keith]

Hi there,

Well done on your success with this interesting project. Bearing in mind the scarcity of the correct valves I think your approach was the right one.

I do have a 2514 which is working with (presumably) its original valves. The (reversible) modification that I have been pondering for many years is to replace the outer cover with a moulded perspex version so the that the amazing mechanical construction can be seen. Maybe one day I'll get round to it!

[Rich Woods]

Originally Posted by boiss

Which Contemporary valves? ( to replace 509K,(K is important) B442 and E415)
Adding the 39K resistor and decoupling cap in series with the regen cct will have minimum effect, ie. the radio will work perfectly by just inserting the 3 correct unobtainable valves, after all the Mosfets and circuits are on sockets that plug into the bases with side and top connections. . Rs and Cs were replaced but they are not visible, and apart from the Main smoothing caps in the big can all values are the original ones. Conversion to more modern valves was a big NO.
"Non modification" I took the easiest route with the minimum change to the basic radio, Anyone with minimum knowledge could undo my little mod and put in a few hundred euros of valves in 5 minutes and be listening.
All the main WW resistors are still in place and only a few high value Carbon? resistors were found to be defective and replaced with hi stab metal oxide resistors (Sorry). Wiring to side connectors (PVC not DSC) Sorry again, and top cap were replaced using original solder tags.
This model radio is a real pain to work on, there are a few faults that can occurr and cause a lot of work. A S/C on the HT causes the Bias pot or its tail resistor to burn out if you are lucky. This means removing the mains tranny and some very careful diss/re-assy of the interior side panel. Re-assy of the box with the interstage and O/P transformer is interesting too!
Anyway enough, If some purist wants to "Give" me the valves I will gladly undo my cct mod and fit the valves. While I'm waiting I will use it as it is now.
Actually that is a lie because I have to make and fit a bottom panel and with a new Philips Made in Holland plaque duly punched.

Don’t get me wrong, I’m far from a purist, I’m very much of the “what’s it matter, it’s working and sounds great” brigade and I am always prepared to modify sets in order to get them going. To me there’s nothing worse than seeing a set non functional and displayed behind glass

What you have done was complete an interesting and easily reversible project with an innovative solution. Keeping the output valve was definitely the correct thing to do as the set will “sound” the same.

To be honest I was smiling more that you have used such modern tech in your work around which in itself is a major, albeit reversible, set of modifications. If there are no readily available alternative valves of the same vintage that could be used without major modification to the set then your approach was clearly the right one particularly in a set of particular historical interest.

[boiss]

Thanks Rich, Keith and Robinshack,
It was just a boat anchor before in a box in the shed, but it has always been at the back of my mind. I have always had a piece of paper in my wallet with the valve Nos and equivalents in case I find one at a flea market. I started working on it a couple of months ago and it has had it's ups and downs. It is superbly made but I get the feeling that the design is the resultof more than one Engineer.
I have been a bit naughty because I added 2 dim yellow leds behind the dials they are connected across the E415 Fil supply with a 1K and are immediately obvious due to the bright heatshrink. Again can be removed by just unsoldering.

I do not have a base panel. I can make one but I would like to know the positions of the holes for the insulated piece that holds the contact safety tongue and the Philips plaque. If anyone has these details I would be very grateful.

I still have the tuning cap going S/C at one point on the dial, probably a bit of corrosion?

These are the plaques that I got made

[boiss]

I also found a neat solution for keeping TO92 transistors cooler. Using Electrical connectors and and pieces of Aluminium. The hole in the connector is just right, a bit of silicon grease lightly tighten the screw etc....

[boiss]

The problem with the s/c on the detector tuning cap was quite easily resolved. there is a screw in a collar on the moving vanes which is pressured / held by a sprung plate.
This means it is easy to move the vanes horizontally by a small amount, I put a bit more pressure on the vanes and voila no more s/c.
I have been looking at a 2514 restoration by a French guy and he gives the measurements of the casing which is 1cm wider than mine, so it appears that there are some variations. Over 10 years ago in Korea I saw some simulated snakeskin covering which had the same pattern as mine. So I bought a couple of metres with the intention of recovering the metal panels eventually. It is a dark blue colour.
I fitted the main cover today, to my dismay the scales were completely dark. The leds I used were very dim , in a dark room I could not discern the dials but playing with a small torch I realised that they needed to be brighter and mounted sideways on to the scale. Backlighting is out because the scale is on top of a black wheel. The scales are quite discoloured but side lighting should do the trick
I need to find some 1mm metal for the base. Might have found a little trick for the Mosfets.

[boiss]

I haven't gone away, just had a few other things causing me to loose a bit of attention on the radio. Tried to get a piece of metal for the base, a real plonker wanted 25 Euros for a piece of steel 20 x 35 cm. So Of course I went for that, NOT!
The screw for moving the vanes can be seen here in attachment.
I have found a neat way of hiding the mosfets and Rectifier. It's ST48.
I'll explain There are some vintage style LED bulbs, On an E27 base shape ST45 or ST48, They are made of plastic, one could also have a top cap attached on the longer one. Ideal B442. However I have looked in the DIY centres and chines places, I only found one but 10 Euros!!! On the web cheaper but must buy 5 or six unless you are in the UK wher you can get a chain for less than a tenner.
Scale illumination not good have changed Leds to white seems to be a bit better.
Cheers for now.

[boiss]

I notice that the LF sound is distorted at medium to high (HaHa) levels, noticed there was no airgap in the O/P tranny, could this be the reason, Quiescent current is about 20mA? The Diaphram on the horn is marked "STALLOY" it is about 0.5mm thick.
M

[Herald1360]

"STALLOY" is a silicon iron alloy often used in early headphones etc because of its desirable magnetic properties.

[Ed_Dinning]

Hi, Zintec car repair plate is about £25 for 1M^2 in UK from car shops.

I have noticed that not all single ended OPT's have air gaps, so try a piece of tissue a max of 2 thou thick. It may reduce the bass notes! You could also increase the neg bias as the valve current may be a bit high at 20mA

Ed

[boiss]

Hi, I imagined it was some special alloy for this purpose, it is actually nearer 1mm thick, I reckon thinner material would have given more volume. I was wondering if the circuitry around the detector might have some bearing on the distortion. As far as air gap is concerned the core is made up of Es and Is which alternate vertically. I've had a little read about core saturation, most opinions go toward a warmer Bass sound with core saturation! I'm going to check the O/P quality of the interstage tranny and look at the biasing of the O/P bottle. It is quite happy with the 2K horn or phones, I tried 800 ohms but the volume was much lower and still distorted.

[boiss]

I found a piece of 0.5 mm galvanised steel at a scrappy from an oven for 1E. Cut it to size and bent it for the base. I need to find someone here with letter and number punches to do the plaque. Also the cover clip needs sorting and a solution for the mains Circuit contact.
I tried to work out the tuning scale frequency correspondence but there are a lot of Spanish MW stations with the same material being transmitted, Using a Sony7600 to identify and listen to the regen, harmonics make it doubly hard. Tuning this is really quirky. Maybe it will be better when the casing is on. Contemporary ATWATER KENT seemed a lot simpler! But so was the wiring! Those radios were a doddle.
Maybe this Zinc plated steel might give me a bit more volume, might be worth a try.

[boiss]

The saga continues. Cut out and bent my piece of zinced sheet. Drilled the holes in the bottom after taking measurements from photos for the Philips label. Due to the angles of the photos the position was wrong. The mounting of the contact plate is a bit complicated because of the internal components of the radio. I decided it was better to make a shorter mount which was then off-centre due to the electrical location in the radio. I then relocated the Plilips plate mounting holes. These will all be covered by the plastic coating anyway. Biggest problem is trying to find some spring material for the sort of clip that keeps the bottom in place, some sort of springy copper/ bronze etc.
I tried the radio with the covers on, it is much better, the regen and gain and controls are much more stable. The Leds I fitted near the scales are a disaster, scale markings cannot be seen in the dark, so I will be removing them.
Seeing as the plastic covering is quite poor I will replace it with the dark blue stuff that I have it is a very similar design.
Back to the Hacker while I search for some spring material !!

[PJL]

Bass requires higher peak to peak amplitude so it might be a good idea to put the output on an oscilloscope to see if you are hitting the limits.

[boiss]

My Scope is in Italy but I can hook up the laptop with the scope software and see what is happening, It's the bass that is rough. I tried the hreadphones on the O/P of the interstage transformer, (Primary Id about 1mA), seemed about the same. Your scope idea is the best bet. The Rs were quite close to the original values, The Cs who knows. I haven't measured the Ia of the O/P bottle but voltages look OK Vg1 is about -21V and the valve is touchable hot.
Getting a bit hot here we have 31C indoors and a fair bit more outside.
I need to find a bottom cover spring solution before opening it up again.
Thanks for the advice.
M

[boiss]

My wife's Morphy richards mixer packed up, speed selector switch. It had fallen into a dozen pieces. Contacted MR but no Spares and no Diagram forthcoming. She hadn't used it for years, it was probably busted then, she bought a 6 speed chinese one for 10E which has been great for the last couple of years, when it breaks it will go in the bin. As for the MR, I replaced the speed switch with a real component with the help of a grinder and WHY. Works a treat.
Back to the point, the switch had 4 little Phospor bronze spring contacts, just the job for keeping the bottom panel on the 2514 in place. Now I need to find some 2mm copper wire to use as pseudo rivets for the Philips plate, Then I can recover the the panel with new simil leathercloth.
M

[Rich Woods]

Awesome bit of “make do & mend”.

[boiss]

Found that I couldn't use the springs to keep the bottom casing in place, just not strong enough. Made a little botchup with a springy bit of steel and a bit of 4mm brass tube, perfik! The part holding the mains contact on the outside of the casing is made from 5mm perspex and the hole spacing is different but the work involved to make the pseudo internals would have involved some tools that I no longer possess. I also left out the hole for the gramophone connection, too many creepy crawlies around here looking for homes.
I covered the base panel in dark blue fine snakeskin pattern plastic with a cloth backing. Not perfect but quite good and similar to the original covering on the rest of the radio. I decided to leave the original black covering material on the rest of the radio. Most of the screws are stainless that are holding the panels on. I removed the useless LED lighting. I am now waiting on ALI Express to sort out the 3 valves, arrival around the end of the month. Radio working very well apart from not hearing anything on LW, Maybe due to local radio smog indoors, which it picks up very well.
Anyway here are the pics of the base and whole RX.
M