CTC 187 Blows Fuse & Reg. Immed.

Have CTC187 that immediately blows fuse and STK730-150 regulator, which
indicates some sort of a direct short. Following
items are good: CRT, Yoke, FRdiode, Caps. Have checked all known
support components along with pin cushion (35"TV). What
gives? Regulator & Fuse blow the second unit is plugged in.
Thanks In Advance,
Jim

 

[john]

What about the HOT and related parts.

kip

--
"Watch the return E-Mail addy its false"
<ozzyman1@sbcglobal.net> wrote in message news:3FD54F8F.C4CE36B8@sbcglobal.net...
Have CTC187 that immediately blows fuse and STK730-150 regulator, which indicates some sort of a direct short. Following
items are good: CRT, Yoke, FRdiode, Caps. Have checked all known support components along with pin cushion (35"TV). What
gives? Regulator & Fuse blow the second unit is plugged in.
Thanks In Advance,
Jim

 

[BWL]

I lately repaired one of these with a shorted 130v diode, along with the bad
regulator IC.

 

[Jason D.]

Have CTC187 that immediately blows fuse and STK730-150 regulator, which
indicates some sort of a direct short. Following
items are good: CRT, Yoke, FRdiode, Caps. Have checked all known
support components along with pin cushion (35"TV). What
gives? Regulator & Fuse blow the second unit is plugged in.
Thanks In Advance,
Jim

OUCH!!

When you find a blown fuse or "dead" set with this STK730-xxx IC, VERY
IMPORTANT to check everything because that IC is harder to find (no
longer made) and expensive.

For CTC176, CTC186/7, like this, always check HOT and the B+ diode,
they tend to short together and kill the IC. Test the flyback and
resolder whole horizontal driver circuit especially remove & scrape
pins on horizontal transformer driver also carefully check that 2.4K
SMD off the horizontal transistor driver.

Cheers,

Wizard

 

[Tweetldee]

<ozzyman1@sbcglobal.net> wrote in message
news:3FD54F8F.C4CE36B8@sbcglobal.net...
Have CTC187 that immediately blows fuse and STK730-150 regulator, which
indicates some sort of a direct short. Following
items are good: CRT, Yoke, FRdiode, Caps. Have checked all known support
components along with pin cushion (35"TV). What
gives? Regulator & Fuse blow the second unit is plugged in.
Thanks In Advance,
Jim

Sounds very suspiciously like you may have a shorted line rectifier,
placing the AC line voltage directly to the regulator, and anything else
that may be in the way. Of course, the fuse is doing its job by blowing
very quickly.

--
Tweetldee
Tweetldee at att dot net (Just subsitute the appropriate characters in the
address)

Never take a laxative and a sleeping pill at the same time!!