KENWOOD TEXIO PD series DC PSU / Free offered Repair tips

[Kiriakos GR]

KENWOOD TEXIO TMI brand or just as TEXIO in our days is a team of people who are dedicated in manufacturing hard to fail DC power supply, so to be used mostly in research and development of electronics which need to be tested for thousandths of hours.

Additionally these hard to fail DC power supply are always the best friend of any repair man, and the story gets even better when it happens to purchase one as used at 1/3 of it true value.

KENWOOD PD series equipment with analog volt meter and Ampere meter are now 20 years old, and this is a message that components aging is now their enemy.

Personally I own a PD35-10 which is undamaged even today and is identical to PD36-10, eve so my PD35-10 is capable for max DC at 37.58V therefore I am suspecting that when these were distributed by RS components, the labeling was changed for unknown reasons.

Today TEXIO seems unwilling to share their knowledge even about their 20 years old models.
And so I made the decision to start this topic,  so any  KENWOOD TEXIO PD series PSU Owner,  to be able to read or add his own repair tip, so others to be helped too.


Repair tip about PD35-10 & PD36-10
Symptom: PSU starts but no DC output
Advice: Unplug the pictured PCB below and inspect the large capacitor for leakage, one Japanese hobbyist discovered that capacitor leakage fluids caused severe damage at the PCB line that crosses under the large capacitor.
With a new capacitor, and after repairing / restoring the continuity at the PCB,  his PD35-10 is back in action.

[giorgos]

Any aged electronic device, needs a capacitor replacement in order to be properly functional for further years.
Especialy in instruments where reliability is primary goal.
Also its good in these situations, to replace , if its possible, all capacitors (not only the faulty one) because their condition is possible nearly to faulty one.
So by this way , we will be more sure, that we will havent to make any another repair in near future.

[Kiriakos GR]

TEXIO Japan have in their website an recently updated Users Manual.
This motivated me so to create later on, one Remote Sensing pair of cables.

When the device is connected to a load, voltage drops due to contact resistance at the
output terminals and resistance of conductors. Remote sensing is performed to
compensate for the voltage drop.

http://www.texio.co.jp/en/pdf/m/PD-AD_B71-0086-01_E_20140120%20.pdf

[Kiriakos GR]

Another repair tip ...

If you need to replace Voltage adjusting potentiometer ?  You will need BOURNS 3540S-1-103L 10K 10 turns.

Beware if you use E bay, most parts sold from China are imitation. 

http://datasheet.octopart.com/3540S-1-103-Bourns-datasheet-9381.pdf

[Kiriakos GR]

This time I did a new discovery,  partially damaged DPDT miniature horizontal button, this could cause issue at ammeter this not functioning at low current.

While I did proceed with cleaning and temporarily restoration, I did find new buttons (this was not easy) and I will order them and replace then in a later time. 

Because of this opportunity about taking apart my power supply, I took several pictures from internals.
This is a huge opportunity so especially young people to see how a true quality build PSU this looks like.
Even me as an expert I did get further impressed by looking details at my pictures.
Entire number of components they are of supreme specifications, internal capacitors inspection shown no damage even after two decades.
Pin headers look silver plated, and there is no corrosion over the PCB or over components.
I got this PSU as used at 1997 and all these years I was unaware that this PSU it got wet due possibly an accident.
Bottom plate was having signs of rust which I did clean and remove due this opportunity of taking it apart. 

[Basbartu]

Hi!

My PD35-10 output switch resigned from duty.

Tried to find suitable spare part without success.

Saw you had issue with switches too and found suitable part.

So could you give me a hint, where to start  looking for it ?


Regards
Juho

[Kiriakos GR]

Hi!

My PD35-10 output switch resigned from duty.

Regards
Juho

Did you dismantle this switch ?
I succeed recovery with lubricating spray for potentiometer.
There is no current flow from it contacts,  inner lubrication gets dry in most cases and reverse action this is not successful.

Yes I am aware of push button spare part code, there is availability in UK. 
This assistance is for members which they have donate and help the Blog.   

 

[Basbartu]

Hi.

Yes, i dismantled the switch and i was about to lubricate it, but noticed that tiny plastic edge from body itself was broken.

Tried to glue it without success, so it's better to look for a new switch.

But thanks anyway.

-Juho

[Kiriakos GR]

Use your camera and post few pictures of your treasure.  (1024x768) 

ON/OFF mains power switch this is not easy to be replaced.

[Basbartu]

Hi,

Broken switch dismantled and it is missing that edge where retainer clip is attached.

Yeah, there is not much space for soldering.


What it will take atleast, is glass of whiskey to improve steadyness of my arm   

[Kiriakos GR]

What it will take atleast, is glass of whiskey to improve steadyness of my arm   

There is a cheaper way, use the regular broom arm as monopod.   

So the problem is actually the push button and not the Mains Power Switch.
If you think to improvise all by your self I would love to see your progress.