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Forum: Pentax K-30 & K-50
02-26-2024, 07:06 AM
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Another poster said John Pye is restricted from exporting the part.
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Forum: Pentax K-30 & K-50
06-20-2019, 11:18 AM
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Forum: Pentax K-30 & K-50
02-21-2019, 07:10 PM
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I see they moved the manufacturing to Taiwan in 1973. Which means the solenoids were made in Taiwan (China) as early as 1973, not Japan.
From the product sheet:
1. The appearance and specifications of the products may be modified without prior notice to improve its performance.
2. This catalogue shows only outline specifications. When using the product, please obtain formal specifications.
3. Please see appendix [How to select solenoid].
4. Please confirm the performance on actual operation by simulation with actual environments for high reliability.
5. Please avoid the storage in dusty environment. If you store the products for a long time, do not keep open the
package.
6. Please take care for the usage in high humid atmosphere and design-in to meet the operating condition of the device,
for the coil resistance increases 0.4%/degree Celsius depending on the operating ambient temperature.
7. Please feel free to contact us for the models with other coil resistances.
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Forum: Pentax K-30 & K-50
02-21-2019, 02:16 AM
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The service manual for the Super Program reads: "The armature must be repelled from the magnet core when supplying voltage to the electromagnet."
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Forum: Pentax K-30 & K-50
02-18-2019, 09:11 AM
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Why not share links to this aforementioned German forum? It's not like there are no other German speaking PF members or on-line translations. People had no problem sharing links to the Russian forums and blogs which started all this solenoid squabbling in the first place.
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Forum: Pentax K-30 & K-50
02-07-2019, 08:46 PM
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So let's see: the drive was made by Panasonic (Matsushita) in 2007. Matsushita allegedly is the manufacturers of the white solenoids. So it would seem Matsushita switched over to green solenoids as early as 2007. Which could mean that anything produced from 2007 on may have green solenoids - that would be late production K10D/K110D, K100D super, K20D, K200D, K-x, and K-m/K2000.
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Forum: Pentax K-30 & K-50
02-01-2019, 08:51 AM
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That's within 10% of 30 ohms which probably within specs. I think the ones that don't work are 15 ohms. But you can always try adding a 15 ohm resister on them.
Obviously different drives use different solenoids. But then people around here seem to take one negative result as a universal result.
Maybe if you list exactly what brand and model drive someone else can take one for the team and check the solenoid in another copy of the same make and model.
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Forum: Pentax K-30 & K-50
11-20-2018, 02:04 PM
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Did you try changing polarity? The Super Program service manual says the wires are pink (+) and gray (-). The wires for the K-50 look like pink and lavender as far as I can make out from the photos and my monitor. The polarity might be different :D
It's also possible that the solenoids in DSLRs have a higher operating voltage. The Super Program runs on 3 VDC where as the DSLRs have what 5-7 volt batteries?
It's been established (from "finely tuned fingers") that the green solenoid requires more force to pull out the armature. Such a precise instrument can't tell us how much of a difference though. And we have no way of knowing how much of a difference will cause failure. Also I don't think any one has compared a working green solenoid vs a working white one for breaking force.
What exactly is aging in the solenoid? Direct and prolonged contact with a permanent magnet does not magnetize metal. The metal has to move repeatedly through a magnetic field in one direction in order for the magnetic poles in the iron to line up. If you ever took a shop class how did they teach you to magnetize a nail or screwdriver? You stroke it across a permanent magnet repeatedly in one direction. I have a horse shoe magnet that is at least fifty years old with a field protector on it - an iron bar across both poles of the magnet. If I remove the bar it is not magnetized - iron filings will not stick to it. Any residual magnetism dispells rapid once it is removed from the field.
So what does that leave us? Oxidation on armature? The insulating varnish on the solenoid windings going bad? The plastic on the coils going bad? It has been claimed that the green solenoids use PET vs PTFE of the white solenoids. PET is very stable. It may not have the same wear resistance as PTFE but age not wear seems to be the problem. PTFE has the edge on PET for UV resistance but how much UV is there inside the camera body. They are about equal for ozone resistance.
Magnets get weaker with age, but it seems either the magnet on the green solenoids is stronger to begin with or the plastic warps or swells thus needing more force to move the armature. Which is perhaps why sanding/filing the armature sometimes restores function if only temporarily.
Again comparing a working green solenoid vs a failed one would be interesting (or not).
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Forum: Pentax K-30 & K-50
11-20-2018, 07:07 AM
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What is the difference between the breaking force, if any, between the two?
According to the Super Program service manual the armature should be repelled from the magnetic core when 3 VDC (pink +) is supplied to the electromagnet. Can you measure the if there is a difference in the force generated by the electromagnet?
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Forum: Pentax K-30 & K-50
10-13-2018, 07:35 AM
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BTW: The Summit Solenoid site says this:
"Add your name to our growing list of satisfied customers including Harley Davidson, Numatics, Zum, Americor, NSF controls, Matsushita, Toray Medical, Asus and Quanta."
So for all we know Summit Solenoid (Summit Elec-Tech) has been the supplier of the solenoid to Matsushita since 1999.
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Forum: Pentax K-30 & K-50
10-11-2018, 08:24 PM
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Remember this source that I found from Taiwan that shows a white solenoid?
Taiwan Magnet Solenoid for Use in Cameras, Cellphones, Stereos and Other Portable Devices on Global Sources
That was dismissed because it couldn't be found in there products catalog on their Summit Elec-Tech website?
Look at this on their Summit Solenoid website custom products:
Solenoid (scroll down to solenoid coils)
and on their home page:
Solenoid
Being a custom product you can probably get the plastic in PTFE, PET or whatever and in different colors. They show an incorporation date of Feb 1999 so they could well have been the supplier of the part since the MZ/ZX-7
BTW: The person selling the used solenoids on EBay claims they were made by ALPS/Matsushita. Going back to Matsushita print catalogs circa 2008, I haven't found the solenoid listed.
(note you have to click on the photo links because they are not via HTTPS)
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Forum: Pentax K-30 & K-50
10-10-2018, 08:21 AM
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The aperture, mirror and shutter movements are all interrelated. If one doesn't complete it's cycle the rest will get locked up too. So, yes, it is probably related. There could be something else failing in the diaphragm control block like the motor for the mirror or some of the gears are broken or slipping. There are also gears for the mirror that can break or slip.
Replacing the solenoid may or may not solve the problem. The only way to find out is to try.
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Forum: Pentax K-30 & K-50
05-17-2018, 04:33 AM
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You said your hand slipped and shorted out another lead. If you shorted the power into another circuit that could cause damage. If not you may have caused a short with foreign material, or by pinching or breaking and crossing wires when you closed the case. Feeling heat when you inserted the battery could indicate a short circuit. Heat in electronics in a very short time where there is usually none is never a good sign.
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Forum: Pentax K-30 & K-50
05-16-2018, 05:21 PM
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I don't know what the internal resistance of your multimeter is but the K10D service manual says to use a 100 to 1k ohm resistor to discharge the main capacitor. I would suggest a 1 to 3 watt resistor just to be on the safe side. If you discharged the capacitor into the main circuitry any number of components may have been "blown" or "fried". The only way to tell is to test each component against the specifications. It's probably easier and more economical to replace the main board and any other ancillary circuit boards that were damaged.
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Forum: Pentax K-30 & K-50
05-05-2018, 10:05 PM
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By magnet are you referring to the permanent magnet near the screw holes or the horseshoe plunger (which should not be a magnet and is the part normally sanded/filed)?
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Forum: Pentax K-30 & K-50
11-04-2017, 05:59 AM
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Ok, let's see you design, build and market a flawless DSLR.
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Forum: Pentax K-30 & K-50
09-19-2017, 07:18 AM
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Search Youtube for "Desoldering". These will go over the basic tools you need - fine tip soldering iron, solder (no acid core), tweezers, de-soldering wick or vacuum (aka solder sucker), heat sink clamps, water based flux.
I would practice on some other broken electronics gear since you have no or little soldering skills. Or find someone with the skills that would do it for you.
desoldering - YouTube
You could just twist the bare ends of wires together and tape them. But taping will be difficult due to lack of space and the connections will oxidize or loosen from the vibration of the aperture, mirror and shutter mechanism. Best to solder them for a secure connection.
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Forum: Pentax K-30 & K-50
08-24-2017, 03:10 PM
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The problem with the magnetism hypothesis is that other posters have reported that metal/iron filings are not attracted to the plunger when they took apart their failing solenoids.
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Forum: Pentax K-30 & K-50
03-03-2017, 09:18 AM
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Excellent! Thank you for taking the time to look at possible causes. The videos are very helpful to.
So you have one with a white solenoid that is malfunctioning? How does that compare to the others?
As I mentioned before (probably in the other repair solution thread) solenoid malfunction can stem from misalignment of the plunger. This leads to wear on both the plunger and sleeve as well. Sanding the plunger is only temporary solution as this does not address the damage in the sleeve. And adding more play to the plunger will lead to more wear. And the alignment issue may not be addressed at all.
Are the parts marked with the country they were made? I've identified a company in Taiwan that makes the solenoids with white or black plastic.
Edit: What position does the green solenoid fail in? I was under the impression it gets stuck in the neutral (power off) position with the horseshoe retracted touching the top plate (magnet end).
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Forum: Pentax K-30 & K-50
02-24-2017, 09:47 AM
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Permanent magnets don't get stronger with age. If anything they weaken. That's why measuring the separation force needed on a "working" green solenoid vs a "failing" green one vs a white solenoid would be useful. The green ones probably use a stronger magnet to begin with. For all we know green vs white is a coding for the strength of the magnet. Measuring the amount of force that the aperture mechanism that withdraws the plunger would be useful too.
Yes, the green solenoids appear to be failing. But the loss of function could be a combination of failures which is maybe why the entire block gets replaced. If you put an unmodified "failing" green solenoid into a working system (swap out the "good" solenoid with a "bad" one) and the system continuing to function normally would indicate a combination of failures.
On the DIY thread there are links to photos on a German forum that shows a metal plate with the solenoid, gear box (with distinctive cross shaped part) and motor. Given other Pentax parts diagrams which show the so-called shutter block to be a plate with a gear box or so-called gear block - a plate with a gear box on it I believe what the German forum is showing is the infamous aperture block.
Time may tell its tale. We will just have to see what the longevity of the DIY filing/sanding repair turns out to be.
Perhaps somebody who has had their camera repaired by an authorized center would open it up and see if the green solenoid is still being used or if it was replaced with a different make/model. This would void the warranty but if it is out of warranty.....
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Forum: Pentax K-30 & K-50
02-23-2017, 08:09 PM
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Too bad madphys didn't install the "bad" green solenoid unmodified into the K100D. That might have told us something if it worked fine without modification. Or if he did I missed it :D
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Forum: Pentax K-30 & K-50
02-22-2017, 07:53 AM
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Or the power circuit could to the coil could drop so not enough current is applied to overcome the permanent magnet. Using AA batteries have less voltage than the Li-ion battery but they may have a lower internal resistance and have a higher current. You'd have to measure the voltage and current between say a K100D, a failing K-50/30 and a functioning K-50/30 to draw any conclusions.
Or the coil itself can be failing. If the insulating varnish on the wire is deteriorating the coils could be partially shorting out resulting in a weaker field (less windings). In order for the horseshoe to become more attractive its magnetic properties would have to change. It has been reported that on failing units it does not attract filings.
Or the mechanical mechanism that pulls the horseshoe out could be failing. You'd have to measure the timing and the force on this part of the aperture block to draw any conclusions.
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Forum: Pentax K-30 & K-50
02-21-2017, 09:26 PM
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It would be nice if somebody took a spring scale (or the like) and measured the separation force between the two different parts and the before and after modified parts.
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