electronics, repairs, service manuals and datasheets discussion community for the repairs professionals and technicians
FAQSearchMembersGroupsRegisterProfilePM'sLogin/Out
Yamaha RX-V563

 
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Equipment Repairs
View previous topic :: View next topic  
Author Message
irobot



Joined: 13 Mar 2009
Posts: 49

PostPosted: Wed Jul 01, 2009 8:20 pm    Post subject: Yamaha RX-V563 Reply with quote

This one has me baffled -

I Have a Yamaha RX-V563, when plugged in all DC voltages seem to be OK. (Power relay energizes as soon as it's plugged in.)

Main ON/OFF button has no effect. Speaker relays do not kick in. FL display stays off, although voltages seem good on the controller, from about -24 to -29 VDC.

The LIM circuitry is functioning, when applying an external test signal.

This problem is very similar to a Yamaha RX-V361 that I'm servicing.

Both these units use the Sanyo STK433-03 and STK433-130 power amp modules.

Thanks in advance for any help !

Mike.
Back to top
View user's profile Send private message
jts1957



Joined: 24 Nov 2008
Posts: 2476
Location: Far, Far Away

PostPosted: Wed Jul 01, 2009 9:57 pm    Post subject: Reply with quote

irobot wrote:
Power relay energizes as soon as it's plugged in.


Let's start with that.

Is the relay driver transistor good? Is the signal from the microprocessor to turn the relay driver transistor on/off behaving normally?
Back to top
View user's profile Send private message
irobot



Joined: 13 Mar 2009
Posts: 49

PostPosted: Wed Jul 01, 2009 11:48 pm    Post subject: Reply with quote

Hi

Thanks for the reply. The power relay driver transistor is good.

The base has about 3 VDC on it as soon as power (AC) is applied, which of course, turns the transistor on and energizes the relay.

I traced the PRY signal. It comes directly off of one of the pins on the DSP (Blackfin) IC.
Back to top
View user's profile Send private message
jts1957



Joined: 24 Nov 2008
Posts: 2476
Location: Far, Far Away

PostPosted: Thu Jul 02, 2009 1:11 am    Post subject: Reply with quote

Can you find which pin tells IC to output PRY?
Back to top
View user's profile Send private message
irobot



Joined: 13 Mar 2009
Posts: 49

PostPosted: Fri Jul 03, 2009 7:14 pm    Post subject: Reply with quote

The PRY signal comes off one of the I/O ports, pin 34 on the CPU/DSP. Normally it's at logic high (3.3V) right after power on.
Back to top
View user's profile Send private message
jts1957



Joined: 24 Nov 2008
Posts: 2476
Location: Far, Far Away

PostPosted: Fri Jul 03, 2009 8:04 pm    Post subject: Reply with quote

Well, does either (input or output) "toggle" along with your command to turn on (or off)?
Back to top
View user's profile Send private message
irobot



Joined: 13 Mar 2009
Posts: 49

PostPosted: Wed Aug 19, 2009 9:43 am    Post subject: Puzzled Reply with quote

Hi again -

After closer inspection, here's what I found:

All power supply voltages are OK with power relay bypassed.

Standby and System Off buttons do not power up unit.

Of course, no display, although voltages on FD pins and controller seem OK.

/PDET, /RESET, PRV1, PRV2, ACDET, VP, THM, PRD, PRI are all OK, although the LIM signal is missing.

Clock signals are all good throughout the DSP board.

Any ideas?

Thanks,
Mike
Back to top
View user's profile Send private message
Drdave



Joined: 11 Jun 2009
Posts: 24
Location: South Florida

PostPosted: Wed Aug 19, 2009 1:46 pm    Post subject: Reply with quote

I hate to say it, but it sounds like a bad Micro.
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Equipment Repairs All times are GMT
Page 1 of 1

 
Jump to:  
You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


eServiceInfo on FB - Service Manuals Free Download - Service Diagrams

Free TV Schematics Download - HARDW.net - Pinout Master - Jabse Service Manual Search - Jabse.InK  - onTap.bg

SnimkiOt.com - Poblizo.com : пътешествия