Tandberg TR2045 recap??

[pari57]

I just finished upgrading the light bulbs.
that is; I took them all out and replaced them for led.
the board that carried the fittings can perfectly be used for reffing the led.

Of course I could have fitted warm white led, so on the outside it would look more like the original,
but since I had the choice, I choose blue led.
They give the machine a real distinguished look.
Beside that, the scale now has blue numbers on top and white in the bottom, really cool.
(Due to the screen printing used on the scale by Tandberg)

The indicator bulb was a bit of a problem, that is to find the best led.
Since led have different spectral patterns I had to do some testing
until I found one that was suitable for the indicator.
but it looks great now. really "sharp"

I will load some pics when I have finished it all.

Beside the looks with the led, it also is a real energy saver.

The light bulbs consume 6 x 200 mA + 300mA for the indicator = 1500mA
The led (20 pcs.) use 20 x 20mA = 400mA
That is only 25%.
I know it sounds crazy, but calculate the costs for the years the machine has done so far ; day after day, there comes something together.
To feed the led a DC current, I fitted a small bridge rectifier and the necessary resistors on the board.

 

[Blue Shadow]

Glad you got that problem sorted. Looking forward to pictures of the real distinguished look of this receiver with the blue LEDs.

What about the power consumed by the resistors in the rectifier? Gotta add that to the 400mA before calculating the electrical savings. I would have used that savings as a way to increase the power output. Something like a "Dang that LED upgrade seems to have added 25 horsepower according to the butt dyno" sort of claim.

 

[pari57]

The rectifier is a B40C800; nothing special.
I had it laying around in the corner somewhere and the resistor 100 ohm 1/2 watt is only there to make sure the voltage and current don't not go wild on the led.
Vac = 6,3 V (see TR2045 Schematic) Vdc= Vrectifier = 4,3 V no caps
the led accept 3,2 - 3,4 V and take 20mA.
Ur= 4,3 - 3,3 = 1 v Ir = 400mA so Pr = 0,4 W (nothing wild)
I had this configuration running for >72hr to make sure that everything is stable.

It looks a little messy when one has fixed everything and as soon as the cover is closed, some led quit service.

Pumping up the output power is not necessary. the machine has a fair amount of output
What makes this machine special is the brilliance and warmth in the sound. not the power.

If I want more Power I will take the TR2080 or any other machine.

But the thought is good
and for sure
taking out the light bulbs does save a lot in power consumption.

regards

 

[jdurbin1]

No, not really - not unless we have a different view of what "a lot" means. It's pretty negligible when you consider the idle current of the output stage and other internal power consumption.

I get it, but would never personally go from the factory design - which is by far one of the better from a reliability standpoint, unlike say Marantz - to something that I had to describe as "It looks a little messy when one has fixed everything and as soon as the cover is closed, some led quit service" - but that's just me.

Kinda falls under the "don't fix it if it ain't broke" rule for me, which I tend to follow pretty strictly.

Nice work sorting the other issues though.

John

 

[pari57]

Thanks for the thumbs up John.
And in general I do agree completely with you.
I like to stay to the original too.
and as you point out their design is seriously reliable.
but isn't most of their stuff ????
okay there surely will be some minor quality products in their product lines,
but in general I believe they made above average products.

In my case here 5 of the 6 bulbs were broken including the indicator bulb, so I had to get new ones anyway.
as I could not get the original frosted glass bulbs anywhere came the idea to switch to the led. I didn't mind a little work.

BTW do you have an idea where I can get some turning knobs for the preset channels
I repaired them with some hotmelt, but it is not my best job.

regards

Paul

 

[jdurbin1]

I apply white frosted glass paint to the correct clear lamps to match the original frosted type. The finish isn't physically as robust (could be but etching the surface to better hold paint just isn't worth the additional labor) so you have to handle the lamps a bit more carefully, but the lighting effect is spot-on. Also have located some suitable wedge sockets that can replace the originals if the plastic has started to crumble with age (I see that every now and then). I also paint the dial indicator lamps red by hand, which is quite durable and presents the original appearance.

Another donor unit is the best bet for the small tuning knobs. Unfortunately they are a bit fragile and when people mistake them for pushbuttons, bad things can happen. I believe the board w/tuning pots/knobs can be interchanged between 2025/2030/2040,2045, 2060 uses same parts but one less pot/knob due to the AM button so not identical unless you are just borrowing the 100 ohm pot or knob.

John

 

[Blue Shadow]

Epoxy worked for making the preset knobs whole again

 

[pari57]

Thanks guys !!
I had the idea that stripping them from another unit would be the only way of getting some "complete" knobs.
but even that is no guarantee for longtime success.
damned !!
I have to put up a complain at Tandberg for using such bad quality plastics.
the stupid knobs can't keep up for some simple 35 years.
what kind of **** is that

 

[jdurbin1]

They definitely could have been stronger... but I think the damage is caused more by people pulling/pushing on them than the knob just breaking on its own. I have a bunch of those models here and the majority of them are intact.

The epoxy solution is fine, given you never really need to remove that knob anyway - whole board just slides out from the back side, pots knobs and all.

John

 

[pari57]

Update...

You probably are right John, I guess I have just bad luck with this one.
Last week I found a TR220 which is even older ) and those where in perfect condition.
But still the plastics get fragile over the years so one has to be very careful dismantling the machines.

so I will see if I can hang some pics to this note



















I am sorry for the bad photo quality, but camera is only a small instant camera with a sh+ty small screen
and since my eyesight is gone really bad lately it was the best I could get.

Sorry for the reflections, but I think you can see pretty good the 2 different colors in the display.
further more do I believe the Indicator is more sharp than with the standard light bulbs.

In the last photo one can see the two smaller Nichicons 10000 uF 50V that replace the two huge Elna's
and of course the Elna Silmic fitting perfectly in there.

To say it myself I am feeling good goooooooooood.

CU