Conion C100 resto

caution

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Some more pics...
The mids blacked out nice too!


The upper tape deck door had a cracked holder so I took the oppurtunity to polish and re-lube the shaft. Giggity.


I went to replace the foam on the battery door, and as I was trying to think of what I could use, I was standing right next to a reel of foam tape that came with the air conditioner I just bought. Perfect!



I also decided to replace all of the dampening strips. I bought a couple types of felt fabric, one was 7 mils thick and the other was 11. The original strips, with the adhesive backing, is 7 mils. I tried to use the 11 mil stuff but it was too stuff to stay down with the double-sided tape.



First I laid down a strip of double-sided tape on the table and applied the cloth. This is a temporary piece to allow clean transfer. Then I would apply a second strip of double-sided tape which would be the one to go on the chassis. This setup also prevented the fabric from veering course as I sliced it. The tape was 1/2" wide so I had to trim all strips from that down to about 0.3". The initial pieces were 6mm and 8mm but I made them all 8mm since I had the room, which gave the tape a better shot at staying down permanently. There are two more on the front part of the chassis which are 10mm wide and will do when it comes back from paint.


It took a lot of lining up to get the bastards on but it all turned out the way I wanted. Did the battery cover too. I noticed it was creaking before I disassembled.









Finally got the heat stakes replaced with a little help from a broken M70 top plate!





The cover just about fell right on it was lined up so well :rock:


Glued the coil back into place before sealing up...


Except for the transformer board, which I'm still using with the chassis to finish the VU backlight, the back is DONE!


And an exploded view... heh heh


By the way big thanks to blu_fuz for a few missing rear cabinet screws, I owe you one buddy!
 

Cpl-Chronic

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caution said:
Just call me Walter :-) haha
I'm so glad I didn't use 35%, I probably would've injured myself and ruined the case. More than once I got some on my fingers and did gave me those white skin burns.

My other tweeter shows up tomorrow, party time! Parts Express shipped me only one, even though it was hand-written on the invoice that they had sent two. They didn't hesitate to send out the other one. Oh and after I bend the tabs through the old holes they will drop right into the old tweeter shells! :rock:

Those tweets will work great. If you notice, the tweeter is inset with a curved throat....that is in essence, a 'waveguide'....the slight horn shape to the throat acts as a slight horn which will boost acoustic output by about 2-3db. Those are perfect & yes, I forgot that I already mentioned these when I posted about 4 ohm tweeters.

Those are the same exact tweeters I used for my SONY CFS-88S Speaker mod & they will not disappoint you I think...

Looks good Caution!! :rock: :rock:

Cpl
 

docs

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Very good thread indeed, thank you caution for taking out your time to post it all here.
Please post a pic of you hoola hooping with the C100 on your shoulder when complete, oh and keep up the superb work.
 

caution

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Thanks Cpl! That's good to hear, yeah I see what you mean now with the waveguide, makes sense! They are six ohms so I might have to attenuate them a bit, I'll have to play it by ear...har har

docs I will only try that with a spotter, and a camera man :-P

OK so over the weekend I got down to business on the VU backlight, a few challenges sort of solved themselves as I got into it. First off I need to have the light above the VUs so space is a very limiting factor. You can pretty much get right up to the front if you bend the leads over flush, but since the case is out for paint I couldn't know for sure. It's likely I'll have the room for the ones I chose but no big deal if I have to grind them down a smidge.

The gizmo store had some new LED strips that looked about the right size so I snagged a couple. They looked great until I got down to the nuts and volts - the LEDs are in two banks of six, and with a 3V drop with each LED, they need 18V. With the AC cord on the box I get ~18.5V. On a wall wart or batteries they wouldn't even turn on. And since the two banks are interleaved, I couldn't just short out a couple and make the drop a more manageable 12V, since even with two of them they wouldn't evenly light up the top. So, saved for another project.

So I fell back on the same ones I used for the dial. With three banks of four, I can use a higher value resistor that will allow minimal change in brightness between batteries and AC. The dial LEDs are a bank of three, so I was forced into a higher resistance anyway, so that looks nice and bright on batteries when I tested it.

The other problem is that light has to get past the meter mechanisms, so whatever I use has to be very bright, but then that makes each LED more apparent, so I need to even it out. Fortunately the top edge of the VU case is ridged, which helps diffuse the light. I had a few laptop displays sitting in the junk pile so I tore one apart and found a bunch of neat things. A couple of the sheets were diffusers, and one of them will split an image after being pulled even a tiny tiny bit away from it, which is exactly what I needed, since I won't have a lot of room to mount the LEDs any distance away from the VU case. I only needed to lay it on the LEDs, the distance from the top edge of the LED to the actual element inside was enough to split the light into pieces that evenly spaced with its neighbors when putting 12 in a row across the top.

Smooshed the stakes down for the battery plate, re-tacked the wire anchor points, and then after work today I stopped over at the shop to see if I could get the felt strips off the front so I could work on making new ones of those, and he showed me the grilles which were already done. Very very happy!! It's got the nice curves on all the holes I was hoping for, just gorgeous. The case is waiting on a different primer since the stuff they had wasn't working. I mentioned that applying a bit of heat has worked sometimes to get the central plate off, but not a huge deal since I'm just getting silver again.

And one other late-breaking development today that I'm honestly a bit ashamed of doing but it will guarantee a fully restored box before summer's over. Don't touch that dial.






 

caution

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Good chance of that :-)

So I bit the bullet on a cutter plotter, I had this idea boppin' around in my head to make a liner for the spare tape tray because of the welding work I had to do on some cracks. I hate cutting things out because it's tedious and never looks perfect.

It showed up Friday and so I I got to measuring out the tray. Just my luck would have it, all of the sub-values added up to exactly the overall dimensions which was a great confirmation I had the right values. Most first-shot measurements came out very close, if not dead-on at a nice round metric value. Except for the overall values, which were a perfect 4"x9", but there's a .05" ridge along the front edge I had to clear.I forgot to add arcs to the tape divider walls but will be simple to add.

I found a nice free open source program called QCAD which lets you draw the outline using relative coordinates, which is what I had all written down so it took like five minutes to draw it. I was afraid I'd have to shrink the entire outline by a few thousandths to allow it to fit more comfortably, but even without doing that it slipped right in!

The backing liner you stick your medium to before loading is so tacky it tore up a sheet of copier paper so I tried a Papa John's flier. I ordered some adhesive-backed vinyl which has a black and white checker pattern, so when I get that I will post more pics. Many many more ideas are coming to mind with this new toy, let me know if you have any :-)




 

blu_fuz

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Cool rig. Looks to be just the right size for re-creating metal trims on boomboxes. I've always wondered what black metal with etched out fonts would look like on a C100.
 

stragulus

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Whow, impressive work Caution. Very thorough and professional, and insightful for everyone else too.

I for one am going to do your sharpie trick on my woofers as well, those came out great! :-)
 

Cpl-Chronic

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This resto is so F'en BOMB-ASS large, it owns the rest, outright! BAM!! Those neo-dymium tweets are sweet eh? They almost fit anywhere with a good sensitivity too....very efficient & cheap...dirt cheap...

Never did the black marker trick. Didn't want to poke any holes in the delicate paper of the cones....

play around with a damping resistor on the mids too to see where you like it. I'm guessing - 3-5db would be perfect as I bet the paper mids aren't notch filtered so a lot of overlap will happen between Mid/Bass & Mid/High as well. Being a 2-1/2" or 2-3/4" tweeter being used as a mid, I bet it is really strong in the 2-8Khz range & is crossed around say 6-8Khz to blend with the woofer & the high end is wide open & overlapping with your tweeter & is going to muddy the soundstage & render the stereo image smeared a bit....also, too bright in the upper mid, it'll scream at you like all C-100's do....

That's why you cross the new tweets at 12Khz to emphasize the high end, keep the oroginal caps for the mids & add a wire wound resistor in series with the mid to dampen the output by about 3db or so.....not sure what value would achieve that. I don't have any real experience with damping drivers for balance. I mostly use filters & active filters....

Cpl
 

jimmyjimmy19702010

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Cpl-Chronic said:
This resto is so F'en BOMB-ASS large, it owns the rest, outright! BAM!! Those neo-dymium tweets are sweet eh? They almost fit anywhere with a good sensitivity too....very efficient & cheap...dirt cheap...

Never did the black marker trick. Didn't want to poke any holes in the delicate paper of the cones....

Cpl
The paper speaker cones in these old boomboxes are so dried out and thirsty, just gently touching the permanent marker pulls the ink straight in! Only very light pressure is needed, I can promise you that.

Before I did the speakers in my RX-5150 last year, the cones were a little fluffy. After the re-colour, the cones were smooth and new looking again. They have held the colour beautifully and still look new.

James.... :-)
 

Cpl-Chronic

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jimmyjimmy19702010 said:
The paper speaker cones in these old boomboxes are so dried out and thirsty, just gently touching the permanent marker pulls the ink straight in! Only very light pressure is needed, I can promise you that.

Before I did the speakers in my RX-5150 last year, the cones were a little fluffy. After the re-colour, the cones were smooth and new looking again. They have held the colour beautifully and still look new.

James.... :-)
How do they sound after the time has passed?