The Workbench

Re: Never change lamps again

classic — Thu, 02 Jul 2009 14:37:47 GMT

yachadm:

Frede

That's a great idea to keep them as original as possible. with the sockets.

Remember you can get the 3mm LED's, which will fit in those sockets quite nicely, once you have removed the original incandescent lamp.

I'd also hazard a guess that you could fit the 5mm LED's in there, if you filed off the LED's wide base collar.

Even with the screw-in metal sockets, after removing the incandescent's entrails, you could solder in a new LED (kind-of like cleaning out the old multiple-capacitor can on vintage-tube equipment, and fitting new capacitors inside).

LED's also come with long leads, so you can fit them like the incandescent's tails.

Menahem

Menahem,

I my 'world' I have to ensure also the customer can replace the part later and still have a fieling of owning an original product. This means I am very dependant of the lamp socket to be 'original' like theE10.

I do follow your point if I had to do an update on one single classic product of my own..

Technical the LED's are justr great and we could have the replacment for years. Actually I was a General Mgr of Electronics parts working for B&O for about 25 years so bying LEDS is really something I have been practicing a bit. But what I see in this actual situation is - now I can get the correct socket for the calssioc lamps.

/Frede

Re: Never change lamps again

yachadm — Thu, 02 Jul 2009 14:25:30 GMT

Andy,

Certainly not ignorance!

A valid question, and one I pondered when I restored my BM3400.

It does not have an S-meter, but 2 lamps of varying intensity to indicate when the FM signal is locked on - high-intensity when off-signal, and low-intensisty when on-signal.

On these two lamps, LED's cannot be substituted directly, without making substantial changes in the circuit, essentially transistorised drivers.

Because these lamps are NOT illuminated at high-brightness when locked on a signal, they are operating much cooler, and therefore have an extended lifetime.

So, I decided to leave only these 2 as incandescents. All others which illuminate at single-brightness levels were switched to LED's.

Conclusion (to answer your question) - it's possible, but IMHO, not practical.

Menahem

Re: Never change lamps again

Jandyt — Thu, 02 Jul 2009 14:01:42 GMT

classic:

the use of the LED for stereo lamp in the old products,

Forgive my ignorance, but can an LED be made to have variable brightness?

Andy T.

Re: Never change lamps again

yachadm — Thu, 02 Jul 2009 10:50:19 GMT

Frede

That's a great idea to keep them as original as possible. with the sockets.

Remember you can get the 3mm LED's, which will fit in those sockets quite nicely, once you have removed the original incandescent lamp.

I'd also hazard a guess that you could fit the 5mm LED's in there, if you filed off the LED's wide base collar.

Even with the screw-in metal sockets, after removing the incandescent's entrails, you could solder in a new LED (kind-of like cleaning out the old multiple-capacitor can on vintage-tube equipment, and fitting new capacitors inside).

LED's also come with long leads, so you can fit them like the incandescent's tails.

Menahem

Re: Never change lamps again

classic — Thu, 02 Jul 2009 09:26:09 GMT

Jandyt:

I'm so sorry I missed this post when you posted it Frede.
Seems like a great solution to a regular problem

Andy T.

Hi Andy,

Yes I am very pleased because I can now soon give a much better reliability of the week point, lamps and still maintain the originality to a high degree of the calssic products.

The biggest problem is the price of the lamps.

I hope to find a solution one day.

/Frede

Re: Never change lamps again

classic — Thu, 02 Jul 2009 09:22:10 GMT

Hi Menahem

I have found the E10 type of LED as you see on the photo above, this lamp I can only find in the 4 std colors plus white. Have found other suppliers of the E10 socket? Perhaps you know of a supplier who deliver to a more atractive price? I am paying between €3 ->€7 right now.

The reason I will use the original socket (E10) is, I would like to keep as close as possible to the original of the products.

By the way I also found this 12V 3 mm wedged socket which are used in a lot of B&O products.

One point I have been studiing a bit is the use of the LED for stereo lamp in the old products, you will need a serial and a parallel resistor as well, but then it works just fine!

/Frede

12v 3mm LED - wedged socket

Re: Never change lamps again

Jandyt — Wed, 01 Jul 2009 16:21:04 GMT

I'm so sorry I missed this post when you posted it Frede.
Seems like a great solution to a regular problem

Andy T.

Re: Never change lamps again

yachadm — Wed, 01 Jul 2009 11:21:02 GMT

Hi Frede,

I have been using LED's on my repairs for years now - I much prefer them to incandescents.

Generally, I sand the LED all around to diffuse the light in all directions, and also Warm-White and Turquoise LED's are now widely available.

The Warm-White is really nice in the older Beo's with needle indicators, and the Turquoise is a pleasant substitute for green incandescents in the later models.

Remember though that some incandescents are in AC (not DC) circuits, and therefore a rectifier diode must be added to the circuit before the LED - that also helps by dropping the voltage by about 0.7V, reducing the size of the required dropping resistor.

Menahem

Never change lamps again

classic — Wed, 24 Jun 2009 12:02:41 GMT

In a lot of the classic B&O products many users know about lamps burning out and the life of a new lamp is sadly also short.

For some of these lamps we now have a solution. This is lamps with the E10 socket. These are used in products of the periode from mid. 196x's like Beomaster 900 - Beomaster 1000 - Beolab / Beomster 5000.

You have to change / insert resistors to make the new LED lamps work in the circuit,but after such a replacement - you will never need to replace the lamp again.

/Frede

The type of lamps