Recap parts list for an MX-110 Z??

So did you get the voltages down? If you want help with the bucking TX let me know and we can make one. Or should the dropping resistors after the rectifiers be increased to bring voltages in line?
John
 
Well....

Terry D. didn't think it would be a problem, but I will prolly put a bucking transformer together for my piece of mind.

Not this weekend though....:drunk: Got buddies coming to town for boys weekend....:thmbsp:
 
Have the FM aligned, I just rotated my 110 back into my system and the FM can be as enjoyable to listen too as a CD, Excellend 3d sound. I've got mine hooked up to my 300B SE amp, I'll keep the MX110 hooked up and will often rotate amps.
 
recap mx 110z

HI,

I'am a new reader of this fantastic forum and I want to recap my MX110.

Here is my list of the elements I thought change :
AES
C-EC50X4-350 Capacitor - Electrolytic, 50/50/50/50 µF @ 350 VDC
C-PD01-400 Capacitor - Polypropylene Film, .01 µF @ 400 V (716P400V103J)
C-RD047-600 Capacitor - Polypropylene Film, .047 µF @ 600 V (715P600V473J)
C-SA10-500 Capacitor - Sprague Atom, Aluminum, 10 µF @ 500 V

Alliedelec
VISHAY SPECIALTY CAPACITORS CAPACITOR, AL ELECTROLYTIC 12 uF 0 TO 250 WVDC AXIAL LEADED -20DEGC 85
Mfr's Part#: TVA1505-E3
Allied Stk#: 507-1110
ILLINOIS CAPACITOR Capacitor, Metallized Polypropylene Film, Axial Leads, 1uF, 400WVDC, 220VAC
Mfr's Part#: 105MPW400K
Allied Stk#: 613-0851
ILLINOIS CAPACITOR
Capacitor, Metallized Polypropylene Film, Axial Leads, 0.1uF, 160WVDC, 90VAC

Mouser
Mouser #: 527-CL80
Mfr. #: RL6606-27.5-92-S3
Desc.: Current Limiters 3 Amps 47 Ohm

Mouser #: 512-1N4007
Desc.: Redresseurs Vr/1000V Io/1A


Did I miss something ?

Thanks.
 
That should get you started, for sure. Can't say that you've missed something since I'm at work with little time to go over the schematic myself.

Would suggest that you redo the power supply first and confirm operating voltages are in spec. Run the amp a bit to know what it sounds like at that stage first. Monitor the power transformer for heating, too. Know what temp it tends to get to after being up for a couple of hours.

Then, I'd suggest you start at the output and work back through each stage. If you can, take a listen at each stage as you work back up the audio chain. I think you'll find it most interesting how the sonics improve as you do this. If not enough time, then certainly redo them all up and down the line. Make sure operating voltages stay within spec and you'll end up with a great preamp!

In this way, you'll know if you missed any caps. Frankly, it took plenty of time using the update/listen/update-next-stage approach. That gave me a time to get any more items I needed along the way.

Cheers,

David
 
Hey guys, love this thread!

I have a beautiful Mx-110 that I've been trying to remedy a problem for the last many weeks.

My Mx is in cherry condition was 100% original until I tried updating a few caps.

I'm trying to keep the unit as close to stock as possible until the needs require a change for repair.

The problem I am chasing is a very low output from my Right Channel in MPX mode. If I stereo reverse, it just moves the issue to the opposing speaker.

In regular stereo I have a balanced volume output. With the assistance of a friend who is quite versed in the field I have tried a few things to no avail.

If anyone has some suggestion, I would greatly appreciate.

I will attach a photo of my Mx-110 insides showing the work completed. First photo is before swapping the caps.
 

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I finally found an MX110z, it should be here in the next couple of weeks...threads like this are invaluable, and I'm sure I'll be looking for help from anyone and everyone who can.
 
I found this thread invaluable as I began work on my MX110z. I finished up the power supply, all voltages are good. As far as the signal path, I've replaced the bumblebee's, and the 1uf electrolytics. I added one CL-80. I'm going to let it play for awhile in my system, and then re-measure the voltages, check resistor drift, etc.

I think I'm going to take my time working through the signal path, I'm not a big fan of wholesale changes. Right I'm feeding it FLAC files through the AUX inputs, and it sounds very nice. The tuner is also exceptional with it's clarity.

Once it goes back to the workbench, I'll replace the festoon lamps/gel and replace the foam behind the glass. Ernie at Audio Classics is holding a new cabinet for me, I think I could use the cabinet from my C33, but I'd rather keep that preamp complete.

I'll take some pics of my work and post for those who might be interested, and maybe keep this thread up top for a bit longer. :thmbsp:

I'm sure that most here already knows this, but I want to say how much a few key people make all the difference to enjoying this hobby. Bill (wgrr) I can't thank you enough for the colored gel, and Terry D. for letting me pick his brain.
 
You really should replace all the electrolytics, since even the newest of those units was built around the mid 60's. I would also leave the power switch turned on, and use a power strip to save wear and tear on the unobtanium switch.

I use both of mine regularly as the tuner/pres for my two main mancave systems. Once you get used to yours, it will be hard to use anything else. But, OTOH, I have a H/K Cit I up next on the bench awaiting a tune up and a McShane PS rebuild. It will be interesting to compare these units....
 
You really should replace all the electrolytics, since even the newest of those units was built around the mid 60's. I would also leave the power switch turned on, and use a power strip to save wear and tear on the unobtanium switch.

I use both of mine regularly as the tuner/pres for my two main mancave systems. Once you get used to yours, it will be hard to use anything else. But, OTOH, I have a H/K Cit I up next on the bench awaiting a tune up and a McShane PS rebuild. It will be interesting to compare these units....

I'm hoping to have it rotated into my system by the weekend. All electrolytics have been replaced, just finishing up the ceramics. It cleaned up well, I'll post some pics when it's done.
I've always been interested in the H/K products, I've got one their A/V receivers in the family room, but no tube gear from them.
 
Update...

All caps done, except the two main multi cap cans.....

CIMG7329.jpg


CIMG7330.jpg


CIMG7332.jpg


CIMG7336.jpg


What value caps did you replace those bumblebees with. I'm having a hell of a time identifying those. 3.3uf?
 
I'm not sure at this point, since this was over 6 years ago. Can you post a picture with the caps in question circled. I do have a 110Z apart on my bench and could look and see what's in there.....
 
I was able to Identify and get my head wrapped around the schematic. I installed the final bits today and powered it up with my variac. I'm having the same issue you had with voltages. Everything seems to be running above spec. I checked and double checked resistors. What did you end up figuring out? One suggestion was to make sure the voltage on C116a was around 225v. I'm not sure how accurate that is as I don't se that specified in the schematic.
 
Do all the MX110 Z models use selenium rectifiers or did later production move to silicon?

Should the selenium rectifiers be replaced no matter what in the MX110? Anyone have a before after picture of the rectifiers before and after replacement. What are new parts to replace it?

Some folks in this thread added a single CL-80. Is that to protect the on/off switch from inrush current?
 
For future reference:

When you replace selenium rectifiers with modern silicon diodes, you often have to place a little series resistance in there as well since the replacement diode will have much less forward drop than an old selenium stack will. Not sure if OP investigated this or not, but if anyone attempts this it should be a pretty hefty sand resistor since it’ll be dissipating quite a lot of heat in operation. I usually buy one of those adjustable ohmites, and leave it set when the power supply hits all stated wickets. Something in the 25 ohm range and about 10-15 Watts will usually suffice.
 
  • Anyone know the values of the striped capacitors in the MX110 Z? Please see below. Is this striped type of capacitor prone to cracking or splitting open? If so, what are recommended replacement parts / brands?

  • In the Z, there are four 0.1 uf 200v Sprague Black Beauties with the red lettering (see below photo). Are the Black Beauties with red lettering mylar difilm that generally don't need to be replaced? I see conflicting info. Some say the red black beauties are paper in oil and must go. Others say they are mylar and should stay.

  • I see conflicting info about an NTC inrush thermistor. Some say, use CL-80 and others say CL-90. Any thoughts on which one might be better suited to preserve the on off switch and to account for increased surge at turn on after the selenium rectifier is changed to diodes?

stripe1.png \\

stripe2.jpg

sprague.jpg
 
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