SX-1010 won't Power On...

[D.E.K]

Done Mark. Parts removed from the PP Board. While straightening the leads, I couldn't help the iron slipping off the tip of the leads a few times. There are a few minor scratches here and there but nothing deep, most important of all, didn't lift up any trace or anything like that. In reality, it looks much better than it does in the pictures. I tried to clean the salt rings after the parts were removed and it looks pretty decent, at last the arrows and (+) can be seen clearly. I will give it another scrub later. I think I will leave it at that because the suspense was enough for one night. If I continue, I might lose my nerve and start getting rough. I am attaching the pictures. Let me know what you think.

 

[D.E.K]

Here is a few shots with some of the replacement parts, conventinal rectifier included, soldered. All except C1, C2, Q6 and Q7. We will have to discuss on those ones. It looks a little dirty and sloppy but I don't think there are any problems with it. It seems to be the residual rosin that is causing it to look dirty as well as the camera revealing too much detail. I am aware that I am going a bit fast but I don't want to stop while I have some momentum gained. If we can confirm those remaining 4 components, I can solder them on, maybe even power up the receiver for testing.

 

[Maron]

Very Nice Job :thmbsp:

Your like a seasoned pro already

 

[D.E.K]

:lmao: Thanks. Let's see what "Sensei" is going to say

I should have bought that iso alcohol.

 

[ccheath]

Very Nice Job :thmbsp:

Your like a seasoned pro already

+1:thmbsp:

 

[D.E.K]

In the picture I retrieved from Mouser is the pin code for the 150v 3a 1w (Vce(sat)=0.3v @ 3a) NPN transistor. According to the pinouts I posted in post #411, E is at the end of the arrow, B is at the opposite end and C is at the remaining hole. That matches your coding ebc in post #406. If that checks out, upon your POLARITY confirmation for the 0.22uf /10v (0.22uf/50v) capacitors, I will go ahead.

 

[markthefixer]

I am confirming that the capacitors for C1 and C2 in the center of the protection board have NO polarity, and can be inserted either way in their respective holes.

And there is no substitute for the picture of the transistor's lead layout. It is the final authority.

The arrow on the Q6 symbol IS hard to see, while the Q7 symbol is now clear.

The capacitors that have been installed already are correct, and it will be easier to solder in additional components if the excess lead lengths are clipped off. I blew up the picture and all but one of the joints look excellent, and the exception could just be a reflection in the picture, it's C6's positive lead (100uf cap) and the reflection makes it look like the joint was a bit shy on solder across the middle of the joint - but like I said it's probably the reflection of light.

With the picture of the transistor's layout from mouser, and posts 406 & 411 you are good to go.


"sensi is pleased"

When Q6 & Q7 are in, a picture of them on the board aimed in from the side at 45 degrees (for the "3d effect") will most assuredly be closely examined.

As for how tiny the transistors are, they really shouldn't heat up, but they are designed for the brief bursts of current they will experience, and the heating from the continuous current of holding the relay in will be minimized by the low Vce(sat) specification of the transistor - they really shouldn't even get warm.

 

[D.E.K]

Here is 2 more shots of the C6's (+) joint. In my opinion it is O.K.

I am on C1 and C2, it should only take a few minutes plus the time the iron takes to heat up of course. In the mean time, you don't go anywhere (not a demand but a request)

 

[markthefixer]

Here is 2 more shots of the C6's (+) joint. In my opinion it is O.K.

I share that opinion. The joint was and is ok, it was the reflection.

I have done many an inspection, and I always end up tilting and twisting both the board and my head to focus well on the joint in question, to avoid the optical illusion that vexed me.

Back at one place I was the only tech authorized by the boss to replace components (especially removing I.C's) and to QC the solder job before it went back into the production stream. Normally the gals that did that all day long were the only ones skilled enough for him. The boss was a crusty, hard a..ed essob that was ex-air force and he gave NO slack whatsoever.

 

[D.E.K]

Okay the iron is hot. I took closer shots of Q6 and Q7. As you said, Q7 is clear and Q6 isn't but after a little bit more scrubbing, we can see the arrow. I attached the closer shots of Q6 and Q7 with my "RED" edit showing the leads. Upon your approval, I will install the NPN's and get it over with...before I pop an artery.

 

[D.E.K]

C1 and C2 are done and they don't look too bad to me. Shall I go ahead with the NPN's (Q6 & Q7) taking guide Post #430?

 

[markthefixer]

C1 and C2 are done and they don't look to bad to me. Shall I go ahead with the NPN's (Q6 & Q7) taking guide Post #430?

Yes, go ahead, your e b c designations are correct.

Before reinstalling the board (when you're fresh, rested and calm), try cleaning (scraping) the salt off of the bodies of the original transistors that are still on the board, the undersides by the leads have to be loaded with salt. It WILL improve operation.

 

[D.E.K]

Mark, I edited post #430. I can clearly see the arrow for Q6 so it's all good.

 

[D.E.K]

All done. Here are the pictures of Q6, Q7 and the final product. Bear in mind that this is a product of somebody who soldered-desoldered for the first time. This way we can eliminate some of the 'frowning' :

Q6 Soldered FOIL SIDE:

Q6 Soldered BOARD SIDE:

Q7 Soldered FOIL SIDE:

Q7 Soldered BOARD SIDE:

ALL Components Soldered FOIL SIDE (Shot 1):

ALL Components Soldered FOIL SIDE (Shot 2):

ALL Components Soldered BOARD SIDE:

ZeroJunk - D.E.K BOARD SIDE:

 

[D.E.K]

G'nite...

 

[markthefixer]

An excellent job.

 

[D.E.K]

Thank you and thanks TO you.

I am on my way to the local drug store now. I'll see if they have some of that isoprophyl alcohol. It also goes under the name of "rubbing alcohol" and supposedly the same thing the nurses use on the area of the skin before they shove in the IV needle and such. I really believe that it might be a big help in removing the salt deposits.

I will be back later and do some cleaning on the Board Side with some alcohol if I can find and if not, with some damp/wet cuetip. Then maybe we can power her up. Do we still need the DBT you think?

 

[D.E.K]

Now some cleaning...

 

[markthefixer]

Congrats on even FINDING that, I have searched long and hard in my area for 99% isopropanol or at least over 70% that they have in the "rubbing alcohol" they sell in the stores, the other 30% is water that magically appears as the alcohol evaporates.

Good luck on the cleaning, you are in untrod territory there, as that's the saltiest equipment I have ever seen.

EVERYTHING in that unit would benefit from being relieved of it's salt coating. You have a bit of work cut out for you.

Frankly I was looking at the pictures and scratching my head as to how to CLEAN that unit effectively. A lot depends upon how well the alcohol cleans off the salt.

 

[D.E.K]

It was over the counter along with other variations (different water/alchol ratio) of it. 500ml for $3.49... what the hey. Though I've done some reading on the isopropyl alcohol and circuit boards and there are a few complaints about it leaving white stains and sticky residue on the board so I will test it on a very small area first and observe the results carefully. Pictures will definitely follow.