David, Did you check this, from Tech Repair CD: MAGNASONIC\MCT2074\NO START* ONLY CLICK-CLICK\\\\REPLACE Q602(2SD1398) OR ECG2302* R628(1 OHM* 1/2W)\\\\\\\\ Jeff -- Intrepid Video TV/VCR Repair 263 S Front St, Steelton PA 17113 717-939-7708; (F) 717-564-4952 www.intrepid-video.com www.tech-repair.net ----- Original Message ----- From: "David Lessard" <mr_fixit@xxxxxxxxxxxx> To: <techassist@xxxxxxxxxxxxx> Sent: Monday, May 17, 2004 12:53 PM Subject: [TechAssist] Re: Magnasonic MCT5301 14" - Dead. No relay click. Shorting relay brings on raster only. NEW PROBLEM! Replaced diodes D602 and D603, now TV cycles ON and OFF when "ON" button is pressed. If "ON" button is pressed in between ON/OFF cycles, TV will shutdown. If I unsolder the AC line from the power relay, TV still cycles ON/OFF and pressing the "ON" button doesn't shutdown the TV. David Lessard Alexandria Electronics 50 Harrison Street P.O. Box 1366 Alexandria, Ontario. Canada K0C-1A0 mr_fixit@xxxxxxxxxxxx -----Original Message----- From: techassist-bounce@xxxxxxxxxxxxx [mailto:techassist-bounce@xxxxxxxxxxxxx] On Behalf Of gulftech@xxxxxxxx Sent: Friday, April 30, 2004 1:27 PM To: techassist@xxxxxxxxxxxxx Subject: [TechAssist] Re: Magnasonic MCT5301 14" - Dead. No relay click. Shorting relay brings on raster only. David, Besides the tip Gary listed, I found this on a similar model: Check R610, 1.8K, 5 wt for increase in value. BTW, replace D602 & D603 with NTE125. Diodes may check good, but replace them anyway. Ken Smith Gulf Technical Services 3034 Gulf Breeze Parkway Gulf Breeze, FL 32563 850-934-8324 (Voice) 850-932-0819 (Fax) On Thu, 29 Apr 2004 23:28:33 -0400 Gary McCartney <gary@xxxxxxxxxxx> writes: > Does the 5V regulator run hot in standby? If it is a 7805 regulator, I > would change it first. Those have a permissable output of 4.75V to > 5.25V. 4.2V is too low. If it's not the regulator itself, then try to > remove loads until the voltage goes back up to 5V. Might also be a > filter cap open. What is the input voltage of the regulator on pin > 1? I > think I remember it has to be at least 1.5V higher than the output > voltage, so you'd need at least 6.5V of well filtered dc on the > input. > > I just found a tip for this model: > > TELEVISION MAGNASONIC MCT5301 DEAD- REPLACE D602, D603 > > Hope this helps. > > Gary McCartney > > McCartney Electronics > Guelph Ontario Canada > Est. 1984 > email: gary (at) number63.ca > > David Lessard wrote: > > > > Dead. No relay click. Shorting relay brings on raster only. Then I > > can press the ON button and everything works fine. I can turn TV ON > > and OFF then ON again so long as I do this within a few seconds. > > Output voltage at IC602 is only 4.2VDC in standby but when relay is > > shorted voltage is normal at 5VDC. There is a tip in the Euras database > > http://www.euras.com/repair_tips_1/Magnasonic/MCT5301/MCT5301_Magnasonic > > .htm on this problem but I'm not subscribed to them. Any help would be > > greatly appreciated; I've spent a little too much time on this 14" > > set already and would like to recover at least some of my lost time. > > As always, thanks in advance. > > David Lessard > > Alexandria Electronics > > 50 Harrison Street > > P.O. Box 1366 > > Alexandria, Ontario. > > Canada > > K0C-1A0 > > mr_fixit@xxxxxxxxxxxx ----------------------------------------------------------------------------- Lost Password: http://www.tech-assist.org and select "Login Problems?". Email Archives: http://www.freelists.org/archives/techassist/ ----------------------------------------------------------------------------- Lost Password: http://www.tech-assist.org and select "Login Problems?". Email Archives: http://www.freelists.org/archives/techassist/