2275 with rarely seen melted dial lamp housing

[wlhd1610]

I recently had a 2275 in for a restoration and was surprised to see a severely melted dial lamp housing.
Usually these are found in 2325's but not 2275's so I thought I would post a few pics....

Closer inspection revealed that someone(maybe even Marantz) had used 300ma fuse lamps which generate considerably more heat especially if also in a wood cabinet....

Thankfully , replacement lamp housing are made by one of our own members here and all is well!

Warm white LED's were used so it will run much cooler now.

Bob

 

[thxdave]

Wow Bob. My 2275 lamp housing had SOME heat distortion but nothing to the extent you have there.

 

[catrafter]

Wow, glad you are replacing the melted mess.
I have seen many melted lamp housings in 2275s, 2325s are almost always melted.
That reproduction is a beauty, is it from AK member lurp?

Tom

 

[Steven Tate]

Those are great looking reproductions. I thought I would have to get one when I worked over my 2325, but I was lucky and it was in pretty good shape. Hopefully with LED's it will stay that way.

 

[onepixel]

What I found in my 2275.

 

[wlhd1610]

Wow, glad you are replacing the melted mess.
I have seen many melted lamp housings in 2275s, 2325s are almost always melted.
That reproduction is a beauty, is it from AK member lurp?

Yes ,it's from lurp.
He is also doing the meter lamp housings!

Two of the three almost impossible to find Marantz parts are now readily available!

Bob

 

[Hipocrates]

What I found in my 2275.

My was exactly like that, and melted too.

 

[lurp]

Yikes, that one's especially bad. Love the before and after pics Bob!

I'm currently working on the next most common housing for the 2285B, etc., but it's really giving me fits. It has these thin, fragile clips that extend beyond the front plane of the housing and designing a single-piece housing has thus far eluded me. I haven't looked at it in weeks, and this thread is a good reminder

 

[fernarias]

Yikes, that one's especially bad. Love the before and after pics Bob!

I'm currently working on the next most common housing for the 2285B, etc., but it's really giving me fits. It has these thin, fragile clips that extend beyond the front plane of the housing and designing a single-piece housing has thus far eluded me. I haven't looked at it in weeks, and this thread is a good reminder

You mean the clips(tabs) that hold the lamp PCB? If it's that then I think it's a bad design and made to fail when you replace the bulbs. I would prefer screws to hold it down like in the earlier designs.

 

[Chrisxo55441]

my 2285B was melted like that as well, AK member Deltalight installed a custom made LED bar in it that looked great. Another thing about those 300ma lamps is they can cause the units to smell, my 2275 and second 2245 both had those in them when i bought them and they both reeked seriously bad , i put 200ma lamps in the 2245 and LEDs in the 2275 and the smell went away

 

[lurp]

You mean the clips(tabs) that hold the lamp PCB? If it's that then I think it's a bad design and made to fail when you replace the bulbs. I would prefer screws to hold it down like in the earlier designs.

No, there are two larger clips that secure the housing to the chassis. I've toyed with the notion of using hardware to secure it, but one of the advantages of those receivers is that you don't have to remove the faceplate to remove / replace the housing. I'd hate to compromise that convenience.

 

[Perkinsman]

No, there are two larger clips that secure the housing to the chassis. I've toyed with the notion of using hardware to secure it, but one of the advantages of those receivers is that you don't have to remove the faceplate to remove / replace the housing. I'd hate to compromise that convenience.

Wow Bob. My 2275 lamp housing had SOME heat distortion but nothing to the extent you have there.

Hi, I'm replacing my housing this week. Would you happen to have or know of a thread with pics of the removal process of the housing?

 

[Perkinsman]

I recently had a 2275 in for a restoration and was surprised to see a severely melted dial lamp housing.
Usually these are found in 2325's but not 2275's so I thought I would post a few pics....

Closer inspection revealed that someone(maybe even Marantz) had used 300ma fuse lamps which generate considerably more heat especially if also in a wood cabinet....

Thankfully , replacement lamp housing are made by one of our own members here and all is well!

Warm white LED's were used so it will run much cooler now.

Bob

 

[Perkinsman]

FYI, the Marantz 4230 model used the exact same part.

 

[icko30]

I'm opening up this old topic because I plan to replace the dial bulbs on all of my marantz receivers. The problem is that 200mA lamps are not available in Europe. We have only 150mA or 250mA available. Because of the cases as described above, of course, I have concerns.
I am not a fan of LED lighting as the greenish tone is more authentic to me.
So I came up with the idea of sticking self-adhesive aluminum foil on the case to reduce the impact of heat transfer. This would of course also change the color of the case, which is age yellowish. That would probably also be helpful.
Any comments on that?

 

[Steven Tate]

If your lamp housing is not warped, you can get rid of that dark yellow reflection by painting the housing with white high heat paint. And you can do it without removing the housing. I did it on this 2275 a few years ago, and it worked great. I did use LED's, but with high heat paint, I wouldn't think incandescents would hurt it.
https://audiokarma.org/forums/index...-my-2285b-project.807017/page-2#post-11268386

 

[icko30]

Hello Steven. I must say that I nearly become master of science reading audiokarmas forum, and I have seen your post some time ago.
I think you did a very good job and I thought about it myself.
But it would seem interesting to me to do two jobs at once, because painting alone would probably not solve the problem of overheating.
(Construction insulating materials covered with aluminum foil comes to mind and I did a little math.)
About color of the lighting, I have another solution. I assume that the 250mA bulb will glow brighter and because of this I will get more bluish tan.
But I was also thinking about a ceramic paint marker with which I could paint the bulb white. But I will deal with this later I would like to solve the problem
of overheating the housing first.
Thanks for replay.

 

[Steven Tate]

I'm not really an expert on incandescent bulbs, but it seems I have read several posts where melted lamp housings were blamed on replacement of original bulbs with 250mA bulbs that generate more heat. Have you found anything like that in your forum search?

 

[icko30]

Of course I came across more threads about it. But one thing is for sure. 300mA bulbs definitely melt the case for 250mA opinions are divided.
Some say they have had 250mA bulbs for years and there is no problem. I think it must be a web of circumstances. Is the receiver in a rack or is it well ventilated and so on.

 

[rBuckner]

I have a 2385 on the bench and it had all working bulbs. Originals plus two 250mA ones. No melting but it was one of the darkest tan colors I've seen! but no melting. I bumped into it and it shattered.

The melted ones I've come across always had 300mA bulbs in them.

Interesting idea on the foil. It will reflect light but will it reflect heat? If so where does it go? Hopefully out the vent holes!