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The flywheel is large solid wheel. Spin it by hand til heads release & reset. Not a bass monster, just very loud. Not the best quality sound for this model.
"Desperate Dad's" Conion C-100F Restoration
Started by
Bloodhound
, Nov 05 2019 09:01 PM
53 replies to this topic
#33
Posted 14 November 2019 - 05:58 PM
No, one direction only. If it feels like something is gonna break, or you hear clicking then it’s the wrong way. Slight resistance is normal because you are driving another gear but once the mechanism is reset, you’ll know because the resistance suddenly drops off over the hump & it’ll seem like freewheeling by comparison. Hard to explain but it’s clear once you’ve experienced it.
#34
Posted 14 November 2019 - 10:46 PM
I also noticed the white spots on the tuning lens. I'm going to assume someone used glass cleaner or some other chemical that caused it. Hopefully I can sand and buff it out.
What do you recommend using to blacken the speakers? A sharpie? Some black printer ink perhaps or is there a tried and tested method?
Don't use sandpaper on the tuner glass. Use Novus #3 for deep scratches, or Novus #2 for fine scratches. As for darkening the speakers, I would recommend DupliColor Vinyl & Fabric Coating, flat black HVP106
#35
Posted 15 November 2019 - 06:49 AM
Thanks for the advice Gents! Most appreciated. This is going to be quite an adventure. Has anyone had any experience stripping paint from the case? I'm used to automotive products mostly so I don't want to use the wrong method or product.
#36
Posted 15 November 2019 - 08:00 AM
The headlight polishing kits work really great on boombox tuner glass.
http://boomboxery.co...x/?hl=headlight
http://boomboxery.co...trash/?p=315694
What not to do:
http://boomboxery.co...-cassette-door/
#38
Posted 26 November 2019 - 10:06 PM
Well, I decided to give my son the Boombox for his Birthday today. He went out of his ever loving mind! 
Talk about jaw hitting the floor! I have never seen that kind of reaction from him and I must tell you it was a proud Dad moment for sure. He actually gave me a hug which is a tough thing for teens to do these days! LOL. I bought him a logitech bluetooth unit that plugs directly into the RCA input jacks and he's been enjoying it with us now for about 2 hours. The more it's used the better it sounds it seems. Unfortunately 2 or 3 small cracks have suddenly appeared that we'll need to address but oh well. Must have been stressed in shipping so I guess that comes with the territory. Still, he's stoked and so am I. He asked me when we can get started restoring it and I told him we'll start on Thanksgiving while mom cooks! LOL. The new antenna's have arrived along with a special delivery from Caution as well! One more expected tomorrow so we're well on our way! Gotta enjoy this time with him while I can. He's preparing a spot for it in his room now and I've explained to him that this could only be possible with the help of some folks here on the forum! He has expressed his gratitude and will no doubt chime in here once we get under way. Thank you again to all for your help and suggestions! This is gonna be a blast! 
#41
Posted 30 November 2019 - 07:52 AM
Thank you for the positive feedback! We got started yesterday and so far we're doing ok.
Got the rear cover removed and thoroughly cleaned. We also cleaned up the power supply. There appears to be rust staining on the power supply here and there so I'm going to try a touch of clr to see if that will clean it up.
The worst has been the cleanup. Goggles and respirators are a must here with the mouse droppings etc. We've got about 50% of it cleaned up. Once we get the chassis removed we should be able to make quick work of cleaning the front case. Thanks to other resto posts we plan on giving it a scrub down in the bathtub as that makes the most sense.
We've got several pictures, notes and diagrams already and every connection is being tagged with the connection and PCB board numbers.
I must say that you folks are an ambitious and talented bunch. Some of the things you do in these resto threads are unbelievably impressive not to mention the reproduction of key parts!
The only let down for us at this point is my son's desire to do a few mods that I am NOT prepared for. I'm old school and like keeping things original. He wants to do a hard install on the bluetooth internally and add a power toggle switch to the rear of the case. He also wants to add LED's.
I have only a novice knowledge in electricity and ZERO knowledge of electronics. I'm giving myself a crash course with a few youtube tutorials but these things take time. I'm sure I can tie into the RCA jacks internally but I'm lost when it comes to tapping into the power supply.
I'm hoping to get as far as adding the bluetooth like he wants. Then I'll tackle the LED's in the future when I'm comfortable and know what in the hell I'm doing! LOL.
Pics coming soon and thanks again for helping us! :)
#43
Posted 02 December 2019 - 12:03 PM
Good for you guys and I love that he is as stoked about it as you are!
I know right? LOL... I think I'm just happy to have an excuse to spend more time with him. Gonna milk it for all its worth! :)
We ran into our first problem yesterday. After a bit of a struggle we were able to remove the chassis from the front case. The tape head mechanism is locked in the up position. It was hitting up against the plastic case edge and appears to be stuck. I tried spinning the flywheel by hand and it it just freewheeled. The belt is melted and all that got me was black fingertips! I managed to push it down by hand just enough to allow the case to slide over it and out while depressing the stop button. I'm hoping I didn't damage anything. The whole of the tape one mechanism is locked up. If there was any lubricant it has no doubt turned to cement. On a good note though the tape door opens and closes smoothly and their doesn't appear to be any damage to the door or springs. Works great in fact! :)
For now we're going to focus on stripping down the front case for repair and repaint. Then we'll focus on the chassis.
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#44
Posted 02 December 2019 - 12:38 PM
Here's the best glue for case cracks. It actually melts the plastic together 
https://www.amazon.c.../dp/B079J4CNJ4/
#45
Posted 02 December 2019 - 05:28 PM
Once you get the new belts on spin the deck by hand a few times just to make sure everything is moving like its supposed to . these have an interlock on the deck that prevent the door from opening if the tape heads are in the play position.
I've had to force these deck doors open before , I just shake the inner chassis until it frees up .
I've had to force these deck doors open before , I just shake the inner chassis until it frees up .
#47
Posted 02 December 2019 - 09:43 PM
This is really a great thing. So nice to see that there are younger folks interested in these things as well. A fantastic eye your son has. He picked the icon of the era for sure. A brave task for your first box restore. I feel confident that you guys will prevail in your endeavor to get this going 100% and looking great.
#48
Posted 03 December 2019 - 01:46 AM
Two questions for anyone in the know, to help with his Bluetooth install.
Question 1: While I was looking into a good spot to patch the Bluetooth audio into, I noticed that the aux/phono switch swaps out the inputs and outputs of the phono amp with a 39k/6.8k voltage divider for aux mode. I'm assuming the Bluetooth module's outputs have either a series resistor or voltage divider as well, but does that matter? Does having two sets of resistors on the audio path affect things in a non-trivial way? You never want to bypass The C100's aux resistors, right?
The red dots would be like plugging something into the back for aux mode, but doesn't disturb phono. Tying to the purple dots does that too, but also bypasses R110 and R111, with R112 and R113 still pulling to ground (updated image with more info)
Question 2: Providing power to the Bluetooth module would be a piece of cake if one only wanted to use it on AC, you could simply install the Bluetooth's wall wart inside the box and be done with it. But trying to attach it to switched power, which is 15-18V, would need some sort of voltage regulator/DC-DC converter to get down to 5V, but does an off-the-shelf solution exist, or would it be best to engineer something out of individual components (5V regulator, heat sink, caps, etc.)
#49
Posted 03 December 2019 - 08:13 AM
Here's the best glue for case cracks. It actually melts the plastic together
Thanks for the tip Reli! Appreciate that! :)
Once you get the new belts on spin the deck by hand a few times just to make sure everything is moving like its supposed to . these have an interlock on the deck that prevent the door from opening if the tape heads are in the play position.
I've had to force these deck doors open before , I just shake the inner chassis until it frees up .
Thanks JVC Floyd. Once the new belts are installed will spinning the flywheel release the tape head from the upward play position? Not sure how else to accomplish that.
This is really a great thing. So nice to see that there are younger folks interested in these things as well. A fantastic eye your son has. He picked the icon of the era for sure. A brave task for your first box restore. I feel confident that you guys will prevail in your endeavor to get this going 100% and looking great.
Thanks for the kind word Transistorized! I think the key here is exposing kids to such things. He showed a few friends some pictures and they've asked to come see it and check it out. Appreciate the vote of confidence as well. With the help we're getting here on the forum we should be AOK! :)
Two questions for anyone in the know, to help with his Bluetooth install.
Question 1: While I was looking into a good spot to patch the Bluetooth audio into, I noticed that the aux/phono switch swaps out the inputs and outputs of the phono amp with a 39k/6.8k voltage divider for aux mode. I'm assuming the Bluetooth module's outputs have either a series resistor or voltage divider as well, but does that matter? Does having two sets of resistors on the audio path affect things in a non-trivial way? You never want to bypass The C100's aux resistors, right?
The red dots would be like plugging something into the back for aux mode, but doesn't disturb phono. Tying to the purple dots does that too, but also bypasses R110 and R111, with R112 and R113 still pulling to ground.
Question 2: Providing power to the Bluetooth module would be a piece of cake if one only wanted to use it on AC, you could simply install the Bluetooth's wall wart inside the box and be done with it. But trying to attach it to switched power, which is 15-18V, would need some sort of voltage regulator/DC-DC converter to get down to 5V, but does an off-the-shelf solution exist, or would it be best to engineer something out of individual components (5V regulator, heat sink, caps, etc.)
I don't know if this helps Eric but I noticed in Teddy Hashee's Clairtone 7980 video at (33:10) he ties into the 15V-18V power supply for tape deck 2 at CN207. Somehow he uses a car charger socket and USB charger rated at 5V. He doesn't appear to have anything in between to step down the voltage. He also wires up to the RCA inputs at a different location on the board. I don't know if the Clairtone is different from the Conion so not sure if this is helpful or not. He does add his own ground loop noise eliminator into the mix as well which is something I was hoping to avoid.
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#51
Posted Yesterday, 07:17 AM
Oh my god I totally spaced the car adapter. They're made to take 14+ volts, good to go!
With any luck it sounds clean straight away.
I've noticed that our Bluetooth units power supply is rated at with 5V DC 150ma output..
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Most of the dual USB charging adapters I can find online are rated at 5V but have much higher amperage ranges. I'm seeing 1.5amps and up. Won't that pose a problem? Again, electronics was like "magic" to me just a few days ago so if this is a stupid question I apologize!
#52
Posted Yesterday, 01:09 PM
Oh my god I totally spaced the car adapter. They're made to take 14+ volts, good to go!
With any luck it sounds clean straight away.
Most of the dual USB charging adapters I can find online are rated at 5V but have much higher amperage ranges. I'm seeing 1.5amps and up. Won't that pose a problem? Again, electronics was like "magic" to me just a few days ago so if this is a stupid question I apologize!
With amperage, the device will only pull what it needs. Now if you went higher in voltage that would cause issues.
#53
Posted Yesterday, 01:16 PM
Most of the dual USB charging adapters I can find online are rated at 5V but have much higher amperage ranges. I'm seeing 1.5amps and up. Won't that pose a problem?
Nope! A circuit only draws as much current as it needs, based on its load. That value is more of a max rating, you can only power circuits that demand up to that much current.
#54
Posted Yesterday, 02:14 PM
Two questions for anyone in the know, to help with his Bluetooth install.
Question 1: While I was looking into a good spot to patch the Bluetooth audio into, I noticed that the aux/phono switch swaps out the inputs and outputs of the phono amp with a 39k/6.8k voltage divider for aux mode. I'm assuming the Bluetooth module's outputs have either a series resistor or voltage divider as well, but does that matter? Does having two sets of resistors on the audio path affect things in a non-trivial way? You never want to bypass The C100's aux resistors, right?
The red dots would be like plugging something into the back for aux mode, but doesn't disturb phono. Tying to the purple dots does that too, but also bypasses R110 and R111, with R112 and R113 still pulling to ground (updated image with more info)
Question 2: Providing power to the Bluetooth module would be a piece of cake if one only wanted to use it on AC, you could simply install the Bluetooth's wall wart inside the box and be done with it. But trying to attach it to switched power, which is 15-18V, would need some sort of voltage regulator/DC-DC converter to get down to 5V, but does an off-the-shelf solution exist, or would it be best to engineer something out of individual components (5V regulator, heat sink, caps, etc.)
Re Question 1: Those resistors are very important because they determine the input impedance that the output source device will see. Obviously, a device which is designed to drive some form of speaker system will expect relatively low impedance but anything that is outputting a line-type of signal will expect to see high impedance of at least 10k Ω or more. You might want to convert that resistor to a lower amount (10k Ω?) but the question is why would you? Most of these consumer DIY type of modules come with very limited specifications so there's nothing to suggest that 39k is too high, and even if it was that is not the only thing to consider, you also have to consider the boombox itself. Some engineer someplace designed that voltage divider system considering not only the input impedance that the source device will see, but also the amount of voltage/current that the next amplification stage will see, and I'm sure they carefully calculated the values of the resistors required for the transistors in the next amplification stage to operate in the middle of its linear active region. Any changes to one factor will require readjustment in others to compensate for the change to arrive at the same result, the subject of which I'm not even going to begin to try to interpret what that was. Simple answer is inject the signal as if it were being injected through the RCAs with all the orig circuitry intact.
Re Question 2: Modern wall warts today are all digital switching PS types. They require a ton of components and much higher investment in design costs to develop compared to analog power supplies, but because the parts in an analog supply, especially the transformer are far more inexpensive, the design costs of a digital supply are easy to fold into and become a miniscule figure when mass produced. However, the downside is that they emit interference that can affect legacy electronics that were not designed to properly shield such interference. Not saying that it will, but it might be a problem. I once calculated the load that one of these bluetooth receivers consume and it's not much. A simple modern voltage regulator IC is plenty robust to supply the needs of the bluetooth device, possibly even without a heatsink, but monitor the heat level with IR temp guage first in operation to confirm. Otherwise small heatsinks are easy to find and cheap to get. An alternative is to just use a simple zener/transistor regulator circuit as used in countless boomboxes and those won't introduce noise but some testing will need to be conducted to see if it can supply the power needs (I suspect it's no problem) in common form, or whether a more complicated design needs to be developed instead.
One other thing to consider. If an internal bluetooth add-on doesn't have it's own function mode but instead is tethered to the line-in jacks, then that circuit will always be bluetooth circuit enabled. Even if it was turned off, the tethered circuits will always piggy back onto that line unless it was switched to cut off the connection. For example, in a normal circuit design, the electronics tethered to any circuit can be untethered by switching such as function or record-bar or muting transistors, etc. It isn't just left dangling even if unpowered. Look at any boombox schematic and you'll see switches everywhere. It's meant to reduce or eliminate the possibility of the unused circuitry to introduce noise. And since the bluetooth really is just hardwired to the line-in jacks anyway, how about just building the bluetooth receiver into a hobby box with a battery pack and just plug in externally onto the line jacks? Would be a simple weekend project, will not introduce any ground loop noise, and easy to connect/disconnect.
