Don't Trust PC-3000 Preamp Rev & Vendor

[Jared]

Just FYI, you really can't trust the WD preamp vendor and revision numbers to be accurate. At least not in older families such as Mammoth. I've got a case here where I tried two different drives which should have been a match according to PC-3000 however, both sets click when in the patient drive. I've retested both sets back in their original donors, and they are still fine so I know I didn't kill them. Original heads don't click in patient drive but are extremely weak, so I know it's not an SA issue causing it to click.

I think the PA vendor/rev is specific to the country. In this case, the donor drives were both from Thailand and the patient is from Malaysia. Off to donor drives to track one down.

 

[michael chiklis]

Hi,
have you checked microjogs value in mod 47 ?
http://blog.acelaboratory.com/pc-3000-f ... #more-1021

https://www.youtube.com/watch?v=bN8uwV7udtI

If the difference between patient and donor microjogs is greater than 300 then donor is not good.
If difference is less than 100 then you have a good donor.

You might try to change microjogs value with those from mod 47 rom patient (follow pc3000 guide).

 

[Sam]

Jared, out of curiosity, did the slider pattern on your donors match the patient?

 

[hdd00]

In those old Mammoth series the manufacturer country was very important when exchanging heads. So i think you should try to find a donor from the same country with patient and don't forget about alignment .

 

[lcoughey]

When matching donors, I don't think I've ever compared microjogs and can't say that I've ever had any issues.

 

[Jared]

[post]5656[/post] have you checked microjogs value in mod 47 ?

Microjogs were pretty close on both donors. But, honestly I've got to agree with Luke here. I rarely find that it matters.

[post]5657[/post] Jared, out of curiosity, did the slider pattern on your donors match the patient?

Didn't actually check them under a microscope.

[post]5659[/post] In those old Mammoth series the manufacturer country was very important when exchanging heads.

Strangely enough, the one that finally worked, was from a different country than the patient. It was the worst matched of the three I tried, and it worked like a charm.

 

[hdd00]

[post]5700[/post] Strangely enough, the one that finally worked, was from a different country than the patient. It was the worst matched of the three I tried, and it worked like a charm.

Strange indeed...

 

[FAsTec]

Hello,

in these cases I'd check out the "Preamp DAC Editor" values

see this screenshot Module 47 - Pream DAC Editor

values which makes even more sense for those WD drives without micro jogs

E.G. in some cases the WD5000LMVW also the WD5000LPVX heads swap can turn into a PIA , yes those 1 platter 2 heads thin drives

I don't know if it ever happen to you

Changed the heads between some 13 - 15 donors while at some point, you find the lucky one that makes things to work like a charm
(no neither reading at least one by one in turns, no way)

Well if any of you have ever done some comparison at Preamp DAC values ... welcome if he/she share his/her experience

I begin right now this experience, since I think it would help so much with some drives

 

[pclab]

So you compare the Preamp DAC values to find a donor match?
This could be helpful when you can't get that info if drive doesn't get ID or bad heads...