I have turned up the amplitude just a little higher than I think it should be. Instead of going into fault mode after loading a pack, the READY light flashes about quickly. With the scope hooked up I can see that it hasn't managed to find the first track yet. Not really sure what it thinks it is doing...
Aaron Jackson via cctalk writes: > Hi Andrea, > > Thanks for your suggestions. > > Checking the amplified output from the r/w heads is one of the first > things I did. The voltages are within normal range, but only after I > push the head a bit further into the pack. > > Although, I did not set the jumper to try the other head (I suppose I > was always looking at head 0), so I've just tried this now. There does > indeed appear to be servo burst data coming from both heads once I've > manually loaded them fully. So I am not sure if this is the problem. I'm > really hoping that the pack is not bad since I paid for a tested pack. > > I also checked the sector transducer output last night. The individual > waves (i.e. from trough to peak) seem to be twice as fast, but the > timings between two peaks is correct. > > The survo busts are correctly aligned with the sector pulses. > > So, from what I can see, the drive should spin up correctly, but for > some reason it goes into fault mode. I am right in thinking that upon > load, the heads should continue moving forward until the first track is > found, right? I should not have to perform a seek manually from the PDP? > If this is not the case, perhaps there is something else wrong. > > Thanks again for your input, > Aaron. > > > > shadoooo via cctalk writes: > >> Hello, >> I'm not an absolute expert, but I successfully fixed a couple of RL02 in >> the past. >> Adjustment to the head is only useful for azimuth, I think. The radial >> position will be adjusted continuously using the servo tracks, so there's >> no absolute position adjustment at all. >> If the drive fails during spinup, I would check at least the following: >> - the presence of spindle sector signal after digital conversion of pulses >> from analog signal coming from the pickup. >> - having disabled the servo linear motor (there's some jumper to setup, >> check the maintenance manual), perform the motor spinup, then load slowly >> the heads on the disk by hand, until you find the servo tracks. >> - with an oscilloscope check the presence of analog signal of the servo >> tracks on both heads, and it's digital counterpart after amplification and >> threshold detection (expected level values in the manual). If you see >> something strange, e.g missing or too short pulses, try to adjust the gain >> with the trimmer on the head board >> - enable again the servo, then load again >> >> My 2 cents. >> Andrea -- Aaron Jackson PhD Student, Computer Vision Laboratory, Uni of Nottingham http://aaronsplace.co.uk
