Help for a Curtis Mathes 3015a chassis

[cocobolo95]

Hi, I'm needing a high resolution color picture of the bottom side of the 3015a chassis. I recently picked this receiver up and it is missing parts and has several wires that are just hanging there not connected to anything.

I have the Sams photofacts for the 3015a. But it does not show the detail that I need to find the connections. I even blew up the bottom chassis view, but it doesn't help me.

Having the wiring shown in color would be a big help. From what I understand, the 3115 & 3215 chassis are the same as the 3015a.

I even sent an e-mail to the Curtis Mathis site on the net. But I received no answer back from them.

 

[cademan]

pics?

 

[cocobolo95]

Her's some pics of Curtis Mathes 3015a

What I need is high res pics of underside of chassis. These pics just to identify the chassis

 

[cademan]

Well if you show us the under side, maybe someone here can see where the wires go. This stuff is pretty simple for me anyway.

To me, it looks like the wires are for the can capacitor, and in which case, is still pretty basic on the connections.

Curtis-Mathes is no longer in business and I presume that the site you are talking about is run by Glenn Waters.

 

[cocobolo95]

Yes, the site by Glen Waters.

I've attached the bottom view and schematic for the 3015a. You are right about the can cap. 4 wires not connected. My concern is which part of can cap each wire goes to.

But my main concern is in the upper left hand side of chassis. Running under the large gray 6800 ohm resistor, R55, is an orange wire not attached to anything. The pic is from the ebay listing, so seller, so wire is hidden. 1 end of wire is attached to terminal strip 2nd from bottom. Where does wire go to.

Also missing are 8 or so oil in paper caps. I've included a pic of the cap chart also. But it's small and doesn't enlarge well.

 

[s-petersen]

If you can get, or scan a better pic of the schematic (power supply area) and a closeup around where the can capacitor is mounted I'm sure we could help you better.

 

[cocobolo95]

I tried to upload a high resolution file of the schematic. Forum said it exceeded 2mb limit for attachments.

I will try to lower resolution to a point where forum will accept upload

 

[Northwinds]

I tried to upload a high resolution file of the schematic. Forum said it exceeded 2mb limit for attachments.

I will try to lower resolution to a point where forum will accept upload

Save the schematic as a jpeg image, upload it to imgur (free account) and then link the url for the image

OR

You can take a picture of the schematic off the screen with a digital camera set at 5 megapixels and upload image to imgur. The picture will be HUGE if clicked on

 

[cocobolo95]

I scaned the schematic at 1200 dpi. It blows up pretty good so you can see everything. However, at over 14mb it's way too big to upload.

If forum has a private message option, you could send me your e-mail address and I would send you the schematic. As long as your server allows attachments that large.

Let me know. And if answer is yes, a quick lesson on how to use the PM on this forum would be appreciated.

 

[Tinkerbelle]

Maybe try printing the schematic as .pdf then attaching the .pdf. The file size allocation is greater for .pdf files.

To do a "PM" click on the members Avatar (Image above the name) or on their name below the avatar, then click on "Start a Conversation" & type away

 

[s-petersen]

Or dropbox is also free, and past a link in the thread

 

[cocobolo95]

Sorry but even a pdf at only 300 dpi, which is the minimum res that file blows up so it can be read, is too big for upload to forum.

 

[cademan]

Hmm, should be pretty easy with the schematic. Now I just need to blow it up somehow.

You can send one to my e-mail. I'll PM you!

 

[century tek]

Hi, it looks like it is pretty much intact. I see a missing can capacitor but that's it. If you think you are missing some coupling capacitors going to the 6BQ5 tube grids, then take a look at a couple of those disc capacitors coming off of the 6EU7 tubes. I'll bet those are the one's that you think are missing. My CM receiver also has the disc style coupling capacitors coming right off of my 6EU7 tubes. I know most designs show a tubular type of coupling capacitor right there at the output tubes sockets but there is nothing that says that they can be mounted elsewhere.

What are the brown disc capacitors coming off of pins #7 of the 6EU7 tubes. Can't read them from here.

Yours doesn't look like it has been pirated except for the can capacitor.........and that's an easy fix.

 

[cocobolo95]

The people who know more on the subject than me, think the chassis is intact. So I will go with that.

It will be awhile before I fire her up. I have to buy all the tubes. And I also want to check all the carbon comp resistors for being in spec.

I thank you all for your help. I will post 2 more pics of the chassis showing the red wire which runs under the gray 6800 ohm resistor in the upper left of chassis. I need some guidance as to where this wire goes. Wire is hidden in my 1st bottom of chassis pic.

 

[cocobolo95]

Here are a couple of pics of disconnected red wire.

 

[s-petersen]

There is a component hidden by the resistor, what it is, and what it connects to, will show where the wire is supposed to connect to.
If it is another resistor, and it is connected to the 6800 resistor, it is easy to find on the schematic
Can you send me the schematic?

 

[cademan]

I can't seem to find that 6800Ω resistor anywhere on the schematic.

 

[cocobolo95]

Under the large gray resistor is R50 @ 330K. It goes to top terminal of term strip where it ties into a180K res which goes to pin 7 of outboard 6Eu7 tube.

Also tied in with the other 2 is a 220K res going to pin 4 of same 6EU7 tube. And large gray 6800 res also tied in to the others at same terminal .

The 6800 res is R55 that is part of power supply.

 

[cademan]

That orange wire goes to the missing can capacitor at C1-C.

As far as I can tell, this Curtis-Mathes receiver is just missing its can capacitor.