Re: Luxman L3 problem
But for mine i dont have switchable mains transformer... The switchable version is the "e" version p2250 ; mine is "s" p2251 (north europe version)
Furthermore on the case there's a sticker with mentionned "1A T 250V"....
Amapola
Member
Last Activity: 04-07-2020, 04:40 AM
Joined: 02-26-2020
Location: Savoie
-
Re: Luxman L3 problem
Yes the fuse f001 dont blown for now.
But i've the p2251 version of transformer so it's the "s" version (for north european country) am in france ; not the "e" p2250. The "e" is multi voltage selector version.
...and according do the schematics it's really 1A T . Furthermore on the case there's a sticker with mentionned "1A T 250V".
I checked again rectifier diode , all have around 0.480v, and off course all in the same way...and nothing in reverse way. So these rectifiers diodes...Leave a comment:
-
Re: Luxman L3 problem
I checked the voltage on the secondary , on the blue i have 40v70 and for the 2 red 31v70... I wanted to be sure, in fact the transformer is not dead at least.
But i saw something strange , on the connection face of one of the 2 big caps 6800uf , i saw white marks, as if there had been a start of burnout...( see pics)
On the other cap, there's no white marks ......Leave a comment:
-
Re: Luxman L3 problem
In all case, for now the transformer dont show sign of life ... I mean just the on/off switch with this transformer...Leave a comment:
-
Re: Luxman L3 problem
Hi,
I desoldered the secondary from the power board ; but for now no sign of life with this power transformer ! When i push "on" , nothing...
In normal work, a power transformer make always a little noise (about 50hz) ; and there 's nothing.
I've also measured the resistance of the primary through the mains plug with switch off "nothing" (there it's normal) and on; I have 11.3 ohm.
But if 11.3 ohms are found in the "on" position, the on switch is ok; true?
So the mistake...Leave a comment:
-
Luxman L3 problem
Hi there,
Suddenly on a L3 220v version (with p-2251 power transformer) i had a blown fuse (f001) 1a.
I just changed this fuse 1 time ; and the same...
I checked on the power board ; all transistors are ok expect q407a and q470b. All diodes and bridge are ok.
I decided to put out the q407a and q408a ; and same for "b".
I placed a new fuse of 1a ...and for now no sign of life...
Anyway , after putting light in my brain... if this fuse has blown, the problem comes from before the fuse...so the power... -
Re: Harman Kardon PM655 - strange values of voltage
between r23 et r49 i have +23.6v and between r24 et r50 i have -23.7v
c23 i have +14.9v and -15v for c24
24v for c21 and -23.4v for c22
the plus and minus for 25v and 15v should be ok
yes i changed c17 and c18 by 35v version instead of 25v ...in fact all the i changed all +/- capsLast edited by Amapola; 02-27-2020, 01:40 PM.Leave a comment:
-
Re: Harman Kardon PM655 - strange values of voltage
I checked i have 237/238vac .
I have 44.4v for c6 and c8 and -44.4v for c7 and c9...
I checked and adjusted the dc balance and idling current too...it's ok for both channel.
...the heatsink of q5 and q6 are very hot for info , hot like this just while the amp was "on" during 15/30 mins for the dc balance and idling adjustment ; because i checked 1 time, i adjusted and leave 15mins again to recheckLeave a comment:
-
Harman Kardon PM655 - strange values of voltage
Hi,
I doing a check in this amp (240v version and the switch is on the 240v ) and saw something strange...
After the schematics (power supply zone) ; instead to have on collector +35.6v for Q5 2SD669 and -35.6 v for Q6 2SB649 i have 40.7v and -40.7v ! For the rectifiers bridges i have 44.8v and -44.8v for both...
For info, all the +/- caps are new ; i even took caps with higher "operating voltage" (if it was given for 16v, i put 25v ...)
Any idea about this difference of 5v ?
Is there someone who spot it too ?
I even... -
Re: New Members - please post your introductions here
Hi there,
Am Amapola ; self taught musician ; and self taught in many other world like mechanic car repair, diy clothes.
Am very curious, patient and i like to find the problem ; so am perfectionist .
I like old hardwear in hifi or music.Leave a comment:
No activity results to display
Leave a comment: