Jump to content

The_Tinkerer

Members
  • Posts

    8
  • Joined

  • Last visited

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

The_Tinkerer's Achievements

Newbie

Newbie (1/9)

0

Reputation

  1. ichigo The blue led in the front is simply a power on indicator, has no reference to whether the unit is receiving a signal. The BASH 300 is a direct replacement for the Sub10 from Klipsch. The Sub10 is a lower power unit but still a good one and should be able to drive the 12" woofer. You can find for $159 at Parts-Express (Dayton)
  2. Well interesting times on this AMP. For some reason as I showed the voltage on the the Big Cap (C58) and TF Pin1 were 152V instead of 90~97V. This bothered me and ties back to a posting by Dr. Vince who had output of 114V I believe. I dismissed it a bit because I had 26.4V across U4&U5 and 5.4V across the two resistors R70&R71 and the light bulb was off (happy). Well after leaving it on for a bit and then turning off and return the next day something happened: The voltage is still high on the Big Cap & TFPin1 165V The voltage across U4&U5 is 24.7V The voltage across R70&R71 is 0.5V R51 lit up in the middle (significant glow) I think Q5 and Z2 went out (beginning to think that Q5 & Z2 went out because of the PDC board). Going to replace the active components on the PDC and then check the resistors which should be good. Following this going to replace Q5 & Z2 and try again. Also looking at the rectifier circuit part, don't know what the components are next to the 230V shunt but they appear to be both shorted when I ohm test in both directions (duh these are 0ohm resistors used as subs on the circuit board machine to make it easier to switch between 115V & 230V systems during fab). HOWEVER, I'm still not sure what reduces the voltage from 165V -> ~95V after the rectifier. ... Interesting revelation, I don't believe there is a voltage reducer before the PDC board for the following reasons: 1) The Big Cap is rated at 470uF 200V which will handle the 165VDC coming off the ACDC full wave rectifier (if using 115VAC), 2) The board has a place for a 2nd Big cap, if you put another (470uF 200) in there (in parallel) the capacitance goes to 400V which (interestingly) will handle the 325VDC if using 230VAC like Europe, 3) The Diode D12 on the PDC is rated @100V which matches with the 90+V on the BASH. I may be off base but it's fishy
  3. Okay, next installment for those interested... After installation of the parts listed in the previous reports, I followed this approach: 1) Visual inspection of Top & Bottom side of PCB 2) Continuity check of primary FET's, PDC pinout and Q5 from the Pin side of the PCB 3) Power up with CL Bulb system with Black line to the end terminal and white line to the terminal labeled N. At this point the bulb glowed bright and contained the issue with the board. I had a 100W bulb in the socket. The board check'd out in step@2, however I missed a continuity check point where Pin4 on the PDC DID NOT attach to Gnd. As you can see from the diagram above Pin 4 should be attached to the source on Q3, however something was wrong (probably a bad through hole when I pulled the board out). The source on Q3 was allowed to float. I connected Pin4 on the PDC to the "pin" near Q3 (there are 2 of them as you can see above) with a small jumper wire. This put Q3 source to ground. I retested the continuity and everything checked out. Re-connected the power source and the Bulb was out... HEY HEY HEY! 4) Performed voltage assessment at the various test points listed in this table. Location Target Reading(?) My Board Comments Big Cap C58 90~97V 152V This filters the High voltage from the Bridge. C58+ (square) to TFPin2 TF Pin1 ? 152V High voltage Primary Pin1 (+) to Pin2 (GnD) PDC Pin2 90V 90+V between Pin2 & Pin1 PDC Pin5 +25.5V + Rail between Pin5 & Pin1 PDC Pin8 - 25.8V - Rail between Pin8 & Pin1 BASH Pin5 12V Pin5 (Vcc) to Pin11 (GnD) (The BASH has full 90V Rail so be careful) U4 & U5 22~25VDC 26.4V Across the Fets from the BASH board. These set the +/- ~15VDC If you don’t have this the PDC is not working. (Chk DIAC) R70 & R71 ~5V 5.4V 2x 150ohm resistors that feed the AMP Mosfets otherside of Board (5x Fets) (Bash Board is good). At idle the Rails should have 5V w/Vol at 0. If voltage is <1V BASH not working Spkr Term I can;t explain the 152V vs. 90~97V, I need to recheck... however I have target voltages in the AMP section. So tommorrow, the plan is to re-check the Main supply high voltage, put the board back together and insert a Fuse and test with a signal. I removed the 4ohm spkr from the cabinet to use as a load and will also put the system output on the scope.
  4. Well, I have re-capped the board. I tested a few of the ones removed and have not found any really bad ones. Replaced: C72 & C74 (these are near the PDC board and looked burned and covered in glue) -> tested at 103.6nF Replaced: C58 (470uF --> tested at 484) Replaced: C48 & C53. Purchased polar by mistake then moved and inserted NP. Should have known in hindsight since this comes from the signal Replaced: C41,C45 C47,C44 C46,C28. This group is the 100uF/35V, 47uF/50V grouping that smooths the AMP rails I believe I completed the Q5 upgrade. ngen33r reco is spot on to handle SMD's. As a bit of side note I purchased a DSO150 Oscilloscope that you have to build. It was a great project to get back into electronics before putting parts on the Sub10. This scope required removal of a SMD shunt. By first using an exacto knife to cut the leg on one side and then using heat (soldering iron) along with tweezers it comes right off. The Q5 transistor was done the same - cut the 2x legs (E/B) then a little heat to the collector and off it came. To install, this was tricky and requires (6) steps (IMO) - not for the faint of heart: 1) Cut the legs to desired "equal" lengths (mine were 8-10mm) 2) shape the legs to the desired geometry... basically putting the legs on the T0-92 in the same configuration/spacing as the SOT, 3) curl the end of the collector leg (90deg) with a pair of needle nose. You want a "VERY SMALL" curl to help anchor into the solder of step4 4) put a little solder on the board on the single leg/pad (collector) 5) put a little solder on the end of the other 2 legs (base/emitter) of the TO-92. Now attach the collector first to the pad and then the base then the emitter "using tweezers in one hand to hold the TO-92 and the soldering iron in the other" - this is the reason to put solder on the legs of the Emitter/Base. 6) Tested the continuity (collector -> C25, Base -> R55, Emitter -> C33) to make sure everything is good and also that the TO-92 is secure (no movement). More to come... Okay, more to add... I have replaced the 4.7uF caps in Audio section near the secondary board input connector. I orginally replaced with polar caps then noticed they should be NP. Also completed my current limiter (courtesy of ngen33r) with a 100W bulb. Tested the continuity to make sure the Hot (Black) goes completely through the bulb to the black alligator clip and the white (neutral) goes from the wall outlet to the white alligator clip. Put the clips together and the bulb is nice and bright. One more visual check and continuity tests and then time for power-up.
  5. Well, I have re-capped the board. I tested a few of the ones removed and have not found any really bad ones. Replaced: C72 & C74 (these are near the PDC board and looked burned and covered in glue) -> tested at 103.6nF Replaced: C58 (470uF --> tested at 484) Replaced: C48 & C53. Purchased polar by mistake then moved and inserted NP. Should have known in hindsight since this comes from the signal Replaced: C41,C45 C47,C44 C46,C28. This group is the 100uF/35V, 47uF/50V grouping that smooths the AMP rails I believe I completed the Q5 upgrade. ngen34r reco is spot on to handle SMD's. As a bit of side note I purchased a DSO150 Oscilloscope that you have to build. It was a great project to get back into electronics before putting parts on the Sub10. This scope required removal of a SMD shunt. By first using an exacto knife to cut the leg on one side and then using heat (soldering iron) along with tweezers it comes right off. The Q5 transistor was done the same - cut the 2x legs (E/B) then a little heat to the collector and off it came. To install, this was tricky and requires (6) steps (IMO) - not for the faint of heart: 1) Cut the legs to desired "equal" lengths (mine were 8-10mm) 2) shape the legs to the desired geometry... basically putting the legs on the T0-92 in the same configuration/spacing as the SOT, 3) curl the end of the collector leg (90deg) with a pair of needle nose. You want a "VERY SMALL" curl to help anchor into the solder of step4 4) put a little solder on the board on the single leg/pad (collector) 5) put a little solder on the end of the other 2 legs (base/emitter) of the TO-92. Now attach the collector first to the pad and then the base then the emitter "using tweezers in one hand to hold the TO-92 and the soldering iron in the other" - this is the reason to put solder on the legs of the Emitter/Base. 6) Test the continuity (I don't remember the attachment points, I will update this later to include that) to make sure everything is good and also that the TO-92 is secure (no movement). More to come...
  6. Good to see that you are doing well and getting back into the hobby u love. My parts arrive today from DigiKey so I plan on getting back into repair. If you get a moment take a look at the photo on the PSU board in front of the BASH board. I'm wondering about Q6 and should I repair along with the Q5 repair. The area looks a little funny to me (discoloration). You can probably use my readings to update the PDC into the second version. Your schematic was correct (and greatly appreciated) just the values indicate (2) versions. I also built and simple current limit light bulb rig and mounted above my work bench area. Planning to install a 250 in the socket which should be sufficient (~2.2Amps which should be good since the AMP uses a 2AMP fuse) Voltage Assessment Location Voltage Comments Big Cap 90~97V U4 & U5 22~25VDC On the AMP section At idle the Rails should have 5V w/Vol at 0 Pin5 BASH 12V To Pin12 (The BASH has full 90V Rail so be careful) R70 & R71 5V 2x 150ohm resistors that feed the Mosfets (Bash Board is good) Here's a table I started of the various voltage test points. Let me know (if u don't mind) if I have this right and other places I should evaluate before heading to signal evaluation. Thanks (The Tinkerer)
  7. ngen33r, you are alive. Yes, I noticed Pin4 on the PDC and need to fix that. I ordered SMD R49 from Mouser along with a couple other parts. I fully tested the PDC and found all parts to meet spec.. Here's a table. I did replace Q11 anyway. If you look at Diodes, do they look ok? The DIAC didn't read a breakdown voltage so you maybe right. The only thing with the PDC board is that only 1 MosFet was blown Q3 along with the Gate resistor (melt'd) R49. Leads me to believe the DIAC maybe ok. So, right now, I plan to: 1) replace the Mosfets Q3/Q4 - done and trace repaired. Continuity verified 2) replace R49 - done 3) replace (update) Q5 - done 4) re-cap the board - done 5) replace TH3 - done
  8. Hello ngen33r, I am posting here in your thread to hopefully get some help. I have a Sub-10 that worked great for years and then no longer was working...I leave the switch in the "auto on" position then turn off the Main Stereo Amp. The system is in my Theater room in the Basement and after my son took over I didn't venture down there too often. Well after some years, a potential bunny rabbit (long story) nibbIing on the power cord and finally a cover falling down on the connector cable (all of this could be coincidence) the AMP no longer worked and the fuse was blown. I replaced the fuse (just to see) and yes - it blew again. So off to the races. I removed the plate amp, but I did not see anything obvious and didn't smell anything in regards to blown components in the power supply. A Google search brought me to this thread. So I disassembled the unit and found the following: 1) The THC (thermistor) looked funny but still read around 10ohms 2) The glue on C72 softened and looked crispy. I think it also got on the PDC board (or something did) and potentially caused a short near Z1 3) I tested Q3 and Q4 and one was good and one was bad. Sooo, before going further, I wanted to review my plan of attack with you... 1) PDC Rebuild replace Z1 & Z2 replace Q11 with MPSA92 (I didn't think the resistors could be bad or the DIAC since if I read your PDC schematic right R1 & R4 tie (go) to the DIAC (D11) and since 1 FET was still good I guess D11 & D12 are good, but I am questioning R1, R2 & R3. These 3 resistors are in the circuit with Z1 where the bad spot on the board was) 2) PS Rebuild Replace IRF730 (I have 730's) Replace C58 470uF cap Replace C27 & (what every the number of the second one is) with panasonic caps (WFA2J 104JE7) Replace TH3 with 10ohm 5A (STM CL-60) This I am a little apprehensive since The original is 10hm 4Amp (160WATTS) and the other is 250WATTS 3) BASH Board Replace Q5 with 2N4401 I'm including a couple PICS to help. Let me know what you think. Thanks for you help.
×
×
  • Create New...