Where can i purchase a service manual for my sony digital8 camera recorder number dcr-trv510

hi,
why do you really need this model in particular?
you can use any Digital8 cam !
here is one:

Sony DCR TRV280 Digital8 Handycam Camcorder 20x Optical Zoom

http://www.electronica.ro/service_manuals/sony/video_camera_recorder/dcr-trv510/
from there, click
Download
DCR-TRV510
pdf user manual option.
hope this helps! let me know how i did

DCR-TRV250E is a PAL version camera of the Digital8 format.
Yes you can use Hi8/Digital8 NTSC tapes. The camera will record a PAL digital picture on the tapes which means that you can play back the tapes in PAL and therefore you will be able to playback recorded tapes on UK televisions because they are also of the PAL format.

Here is a link to get a manual:

http://www.docs.sony.com/release/DCRTRV510.PDF

After you open it, save a copy to your computer for future reference.

Thanks for using Fixya.

hi,

see if the sony cam manual you need was on this list:

The Sony DCR-TRV480 and DCR-TRV380 Digital8 Manual can be downloaded at: http://www.docs.sony.com/release/DCRTRV480.PDF

The Sony DCR-TRV460 and DCR-TRV361 Digital8 Manual can be downloaded at: http://www.docs.sony.com/release/DCRTRV460.PDF

The Sony DCR-TRV280 Digital8 Manual which also covers the Hi8 CCD-TRV138 and CCD-TRV338 can be downloaded at:
http://www.docs.sony.com/release/DCRTRV280.PDF

The Sony DCR-TRV260 and DCR-TRV265 Digital8 Manual which also covers the Hi8 CCD-TRV128, CCD-TRV228 CCD-TRV328 and CCD-TRV428 can be downloaded at:
http://www.docs.sony.com/release/DCRTRV260.PDF

The Sony DCR-TRV130 Digital8 Manual can be downloaded at: http://www.docs.sony.com/release/DCRTRV130.PDF

The Sony DCR-TRV240, DCR-TRV340, DCR-TRV740 and DCR-TRV840 Digital8 Manual can be downloaded at: http://www.docs.sony.com/release/DCRTRV840.PDF

Sony DCR-TRV510 is digital handycam and records video signal in digital format on tape.
Digital Video signal requires a software Picture Package installed in PC to transfer files. You can check camera box to find software cd for the same. 
You also need to hook camera trough iLink port to  iLink / DV port in PC. You can find details in user manual of handycam and still need help, let me know.

here you go

DCR TRV140E is a Digital8 camera
CCD TRV87E is a Hi8 camera,
(Hi8 is an analog format)
the tapes are the same size, wont help, the recording systems are not compatible
send them to a lab service ?maybe if there are only a few
or ebay a Hi8 camera and transcode them yourself

its not a solution, at least it clarifies the problem

I believe all Sony model DCR-TRV2XX and 3XX would play Hi 8 and ST8
Such as DCR-TRV265, DCR-TRV285 DCR-TRV340, DCR-TRV355
I hope that give you some ideas

mechanical alignment! try to record for a minute and playback the result on another player/recorder, not on your camera, if the playback is not okay then your camera needs alignment, you need pro fix. You said that you've done manual cleaning already, maybe you dis aligned the mechanical parts accidentally, applying too much force on the mechanical parts of your small unit tends to bend, dislocate or move these parts out of alignment. defective videohead will never playback good video, and you said that it seems to correct only a few minutes of playback.