Hi everyone!
I managed to get my hands on a rough condition B&K 707 for "the best price" because it was not working. It's my first tube tester and I'm really wanting to get it up and running. I downloaded that manual that has the schematics and tested every resistor and capacitor and replaced the ones that failed. I replaced the missing 83 rectifier tube with a used but tested-good one. I also have a number 80 rectifier tube that I have used in tests before I found the 83 tube.
Initially I noticed that I was not getting the red on-light to turn on, but it...
DCJack
Member
Last Activity: 03-05-2024, 06:06 PM
Joined: 04-09-2013
Location: West Kelowna
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B&K 707 tube tester. I need help.
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Trouble finding Samsung ba41-02176a boardview
Does anybody have access to, or know where to find a board view for the ba41-02176a mainboard from a Samsung Np510R5E laptop? -
Re: I'm having trouble identifying a SOT by its markings.
That's what I managed to find as well but that missing M from the makings is causing me concern.... -
I'm having trouble identifying a SOT by its markings.
I have what I think is a SOT-23 with the markings A1 M on it and the closest I can come up with it that it's a Philips 1N4148 but only if I ignore the 'M'. I've included a picture of the diode.
Anybody have any good SMD identification resources they want to share?
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Re: I need some help identifying a crystal.
It does not make any noise when I shake it, no....Leave a comment:
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Re: I need some help identifying a crystal.
Well that was quick, thanks. How did you figure that out?...Leave a comment:
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I need some help identifying a crystal.
I am trying to fix a friends "bow string weight guage", basically an electronic scale that hooks on to a string. It slipped out of his hand when he was testing a bow and shot it across the room into a wall like an arrow. Everything looked fine but the unit won't turn on now.
I took the thing apart and can't find any physical damage and all the components pass my DMM sniff test and from past experience I know that crystals can fail due to shock damage much more easily than other electronic components. I'm hoping to replace the crystal and be done with it because if it is... -
Re: Trying my hand and BGA re-balling and I can't get the balls to stay put.
What I meant by get stuck is that they seem to be sticking, as in adhesion or static cling....Leave a comment:
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Trying my hand and BGA re-balling and I can't get the balls to stay put.
So here is my story. I decided I wanted to play around with some BGA re-balling and bought myself a "BGA re-balling kit" that came with the following:
[LIST][*]Re-balling station (the blue one with spring loaded base and black handles)[*]AMTECH RMA-223 flux[*]assorted stencils[*]assorted balls[*]solder wick[*]brushes[*]scraper[*]kapton tape[/LIST]
I am trying to re-ball an ATMEL Cyclone III chip and I can't get the balls to stay put when heating with my hot air SMD wand (minimum air flow). My process is as follows:
[LIST=1][*]Mount BGA chip to re-balling... -
Re: Mini PCI diagnostic cards
I bought that exact model but all it ever displays is "0", even on working laptops.Leave a comment:
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Re: Del N5010 not powering up. CK=DC chip burning hot.
Looking at the schematic I see that PTC4603 has a source voltage from +5_PWR. I can't find anywhere on the schematic where this +5_PWR is being generated. I want to start tracing components from this source.
Another interesting thing... Even though the +3.3v_ALW is shorted as shown by PTC4602, to ground the power button has it's 3.3v trigger.Last edited by DCJack; 06-07-2013, 05:39 PM.Leave a comment:
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Re: Del N5010 not powering up. CK=DC chip burning hot.
[U][B]Ignore this post, Pin16 is no longer shorting to ground.... I am so confused.
[/B][/U]
Found something interesting...
When I measure pin 16(VIN) on PU4601 it shows short to ground and Pin8(VREG3) and Pin 17(VREG5) do not show short. How is the chip getting hot if there is no power getting to it because of the ground short at pin16?
P.S. I found the schematic...Re: Del N5010 not powering up. CK=DC chip burning hot.
[U][B]Ignore this post, Pin16 is no longerLast edited by DCJack; 06-07-2013, 05:02 PM.Leave a comment:
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Re: Del N5010 not powering up. CK=DC chip burning hot.
Both of the caps test good out of board but the contact points show continuity to ground.Leave a comment:
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Re: Del N5010 not powering up. CK=DC chip burning hot.
I lifted all the large filter coils (was incorrectly calling them chokes) and the chip(Label 1 in image) is still burning hot, so I removed it. When I applied power back to the board the left most FET(Label 2 in image) became burning hot, so I removed it. Reapplied power to the board and the right most FET(Leble 3 in image) became burning hot to the touch. I replaced all the components I removed but kept the coils lifted and now write this post.
Should I keep going?...Leave a comment:
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Re: Del N5010 not powering up. CK=DC chip burning hot.
I am doing some Googl'ing trying to learn how removing the chokes will help me find my short. I feel like I'm missing some basic electronics principle.Leave a comment:
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Re: Del N5010 not powering up. CK=DC chip burning hot.
How did you guys find out what the chip was by the little information I provided. I must learn your secrets!Leave a comment:
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Re: HP G61 with momentary power
Replaced it and they all lived happily ever after.Leave a comment:
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Del N5010 not powering up. CK=DC chip burning hot.
I'm working on an abandoned Dell N5010 that looks to have good power and the power supply sounds good, but when power is triggered the power supply squeals.
I took the board out and powered it on the bench, everything measures good, all FETs pass, but there is one chip that runs burning hot. It is a tiny (probably 4mm x 4mm) with the following markings:
Line1: CK=DC
Line2: H1Q
Line3: .
The third line is obviously a "pin 1" indicator. Plugging the codes into Google gives me nothing useful and I have never come across this chip... -
Re: HP G61 with momentary power
Found the problem! It turns out it was a bad coupling cap that was not quite shorted. It was a lucky find as it burned me when I was measuring something on the board.Leave a comment:
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Re: Toshiba C655-S5128 power problems
Have you tested the power supply under load? I would do some power math and figure out what value of resistor you would need to almost max out the current rating of the power supply and use an appropriate power rated resistor (more often then not a flame-proof resistor) to short the DC output of the power supply and check to see if the proper voltage shows on the volt meter.
If the power supply passes the load test I would the check all the FETs on the mainboard for shorts (majority of the 8-pin ICs on a laptop board are FETs)....Leave a comment:
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