2 TE's, Different Strokes

Slypty · 04/08/2015, 11:03 AM

The pic below shows how I blew off a small electrical part (resistor? Can't tell.) with a hot air soldering station. I probably should have done this job with a regular iron, anyways what's done is done. The missing part (below the - Leg of the Blue Cap) has 7227 written on it. Anybody know where I can find a replacement? I have a few broken SNES's that have very similar pieces, but I don't know if I can just swap 'em.

The second pic is of a different TE board. It was intermittently working prior to replacing the Video and Backlight caps. One of the backlight Caps has a lifted tab, but it is still attached to its trace, so it should still be functioning. The Cap is placed to some holes which appear to be on the same traces, but that didn't work either. I get a black screen, and I don't think I did much wrong here.. if anybody sees something I'm missing, please comment. I have a Capacitance multimeter, and following the guidelines both Backlight Caps have a peculiar value of 200.. I don't know what that means, I'm not testing current, and I can't imagine it being Voltage. A little new to testing Caps.

thesteve · 04/08/2015, 06:51 PM

first pic your missing the monitoring resistor for the -24V supply (dont recall the value)
second pic try shooting a larger area

Fidde_se · 04/09/2015, 06:43 AM

Are you sure it's 7227? Look on the other one, otherwise that means 4.5M Ohm

Fidde_se · 04/09/2015, 06:45 AM

http://pages.ebay.com/link/?nav=item.view&id=251907573169&alt=web

Fidde_se · 04/09/2015, 07:05 AM

Forget the last one it was suppose to be 7.2 G ohm, which I don't think it is, gonna check R502 later

Slypty · 04/09/2015, 07:58 AM

Quote from: Fidde_se on 04/09/2015, 07:05 AMForget the last one it was suppose to be 7.2 G ohm, which I don't think it is, gonna check R502 later

I'll take a closer look, it's hard to see.. .will bring out the magnifier. It could be 2772 as well.

Fidde_se · 04/09/2015, 08:32 AM

27.7K sounds better at least

Slypty · 04/09/2015, 11:25 AM

I looked closer at it, and the best my eyes can tell which isn't great, is 272.. possibly 27.7 as mentioned.

I've measure the two Backlit Caps on the other crappy pictured TE, I'm pretty sure I have a broken positive trace on the one closest to the Video Cap.

The measurement for the Back Cap charges at about 3.7 and then stops at a value of 15.8, which seems right on the 16V Cap. The other charges the uF at the same rate, but the value is always wonky and changing.. does that indicate a broken trace? Does anyone know if there's a good place to replace that Caps positive trace? Thanks

Slypty · 04/09/2015, 12:08 PM

Man what a waste of time, I've been testing my Caps with a Multimeter that only measures the time it takes to charge and discharge. It has a 'Capacitance' setting, but it doesn't measure the Cap Values, it measures 'time'...

Which in some way is useful. Do I need to get an in board ESR meter to test the Caps?

What I need to know is if the traces are broken, my Caps are brand new so I doubt they are bad. If I'm testing Caps while they are in board, does a bad Cap value mean that it could possibly be a bad trace? In other words, how am I to test a bad trace by testing an in board Cap?

Fidde_se · 04/09/2015, 12:14 PM

it's 272, (2.7K) 0805
this a little more then you need but the price isn't that big
http://www.aliexpress.com/item/Free-Shipping-500PCS-0805-2K7-2-7K-OHM-5-smd-resistor/32247344967.html

Slypty · 04/09/2015, 12:34 PM

Thank you! I'll grab one.

Quote from: Fidde_se on 04/09/2015, 12:14 PMit's 272, (2.7K) 0805
this a little more then you need but the price isn't that big
http://www.aliexpress.com/item/Free-Shipping-500PCS-0805-2K7-2-7K-OHM-5-smd-resistor/32247344967.html