rca ctc1698f: Page 4


	FORUM HOME	SEARCH POSTS	WHO'S ONLINE	LOG IN	RULES F.A.Q.

TV Forums: TV Equipment: TV Repair Forum:
rca ctc1698f

1 2 3 4 5

View All

Print Thread

kingm316
User

May 16, 2010, 11:34 PM

Post #76 of 115 (1701 views)
Shortcut

Re: [jts1957] CTC169 Dead set... [In reply to]	Can't Post

i hooked a jumper wire to the ground and to my meter and put my positive lead on pin 38 of u3101 and with it plugged in only it has 0v i used the remote to turn on and the voltage went to 4.75v for about one second and then went to 0v and did this for a total of five times. out of curiosity i checked pin 26 of u1001 and it was 8.82v for a second and went back to 0.54v and stayed there.
i don't know if i mentioned this or if it even matters but i have not heard the degauss relay click during anything i have done to this tv if that means anything to help you.

(This post was edited by kingm316 on May 16, 2010, 11:37 PM)

Ron.M
Veteran

May 17, 2010, 5:45 PM

Post #77 of 115 (1691 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;.....

OK , next;....
Remove Q4401 (Horiz output Transistor) from the chassis...
Repeat reading at Pin 38....Count how many times the 5 vdc starts up....
When it stops , unplug the TV for about 5 min's or so....
Plug the TV back in & read the volts on the chassis collector pin for Q4401....
Turn the TV on & see what that voltage changes to....

Later....Ron.M.... Cool

....
Veteran & Retired TV technician

kingm316
User

May 17, 2010, 9:23 PM

Post #78 of 115 (1684 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

i removed q4401, plugged in tv and the collector of q4401 was 142.4v. i then rechecked pin 38 and it went to 4.7v to 0v a total of 4 times. unplugged it for 5 minutes then rechecked the collector of q4401 and got 142.5v, then pressed power and it jumped to about 157v and fell to about 144v, did that a couple times then returned to 144v.

Ron.M
Veteran

May 17, 2010, 10:57 PM

Post #79 of 115 (1678 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;....

From post #68;...

Quote

jts no i did not have 5v on the emitter of q703 when i pressed power, which is what i think you mean when you say run. but those 3 voltages i just took were with the set just plugged in and i did not press power at all.

Did you or did you not have 5 vdc on the emitter of Q4703 when you pushed power on ???....
If you don't remember go back & re-check it....

Later...Ron.M..... Cool

....
Veteran & Retired TV technician

kingm316
User

May 18, 2010, 12:50 AM

Post #80 of 115 (1673 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

yes ron, before on q4703 the emitter was 0.3v while plugged in and it jumped from 0.8 to 0v and cycled like that a few times when i pushed power before, i took notes when i measured it before. but i also rechecked it now with the horizontal output transistor removed and just plugged in there is .33v on the emitter of q4703. when i push power it goes to 0.13v then pretty quickly to 0.46v for a second then 0v and then cycles a few times and then stops at 0.33v and stays there.

Ron.M
Veteran

May 18, 2010, 9:14 PM

Post #81 of 115 (1662 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;.....

Right under these "Xs" & slightly to the left of the 1st red arrow is Q4702......

................XXXXX.....

Check the connections & make sure they're OK....
IF in doubt , re-solder base , emitter & collector connections....
Plug in the TV....
Read the volts on emitter , base & collector with the set OFF....
Then push ON one time ONLY & read the volts again & post results.....

THANKS.... Laugh

....

Later...Ron.M.... Cool

....
Veteran & Retired TV technician

(This post was edited by Ron.M on May 18, 2010, 9:17 PM)

kingm316
User

May 19, 2010, 12:52 AM

Post #82 of 115 (1654 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

the connections look good but i resoldered them anyway. while just plugged in q4702 is
c was 12.83v
e was 0v
b was 0v
pushed power and it is
c was 12.7v
e was 0v
b was 0v

Ron.M
Veteran

May 19, 2010, 2:37 AM

Post #83 of 115 (1650 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;....

OK ...next.....
On this same drawing just below & to the left of Q4702 you'll see Q4705....
It's a lot smaller than Q4702....
Do the same as you did for Q4702....
Read emitter , base & collector of Q4705 with TV OFF , then push power one time ONLY....
Unplug TV & wait OR SAFELY discharge the 140 vdc that goes to Q4401 (Horiz Out Transistor)...
Re-install Q4401....
Re-test the voltages of Q4705 with the TV off & then again with the TV turned ON....

Post readings for Q4705 TV OFF , TV ON without Q4401 installed...
Post readings for Q4705 TV OFF , TV ON with Q4401 installed....

Thanks.... Laugh

....

Later...Ron.M.... Cool

....
Veteran & Retired TV technician

(This post was edited by Ron.M on May 19, 2010, 2:42 AM)

kingm316
User

May 19, 2010, 12:09 PM

Post #84 of 115 (1642 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

ok, without q4401, q4705 is
tv off
C is 0v
E is 0v
B is .74v
pressed power and is
C is 0v
E is 0v
B jumped from 0.74v to 0v a couple times
with q4401 installed q4705 measured
tv off
C is 0v
E is 0v
B is 0.74v
pressed power and is
C is 0v
E is 0v
B jumped from 0.73v to 0.02v a couple times

knutnhuny
New User

May 19, 2010, 1:44 PM

Post #85 of 115 (1638 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

hey,
Ron.M I've read most of this thread and you seem to know what your talking about. I'm having a similar problem with my TV. I posted on this forum about it, I'm not sure if you've seen it but here's a link to it http://www.tv-forums.com/cgi-bin/gforum.cgi?post=72098;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;guest=16559967
At this point I'm not really asking how to fix the problem. I just want to have some idea as to what could be causing the problem. If you and anyone else reading this has any ideas I would be extremely grateful for your help.
Thanks

jts1957
Veteran

May 19, 2010, 4:47 PM

Post #86 of 115 (1633 views)
Shortcut

Re: [knutnhuny] CTC169 Dead set... [In reply to]	Can't Post

Ron "sees" everything. Cool

This set: 90's three CRT rear projection.
Your set: Late 2000's LCD display.

No comparison. Totally different technology. Unimpressed

-------------------------
Location: Far, Far Away

knutnhuny
New User

May 19, 2010, 5:45 PM

Post #87 of 115 (1630 views)
Shortcut

Re: [jts1957] CTC169 Dead set... [In reply to]	Can't Post

Yeah I know jts1957 but I'm not getting any power to mine either. So I thought maybe someone here could help. You seemed to know some stuff too you got any ideas about what could be wrong or any ideas as to where i could find some help?
Thanks

kingm316
User

May 19, 2010, 6:21 PM

Post #88 of 115 (1623 views)
Shortcut

Re: [knutnhuny] CTC169 Dead set... [In reply to]	Can't Post

actually jts, it is i think from 92 but it is not rear projection, it is just a big 36'' single tube if that matters

Ron.M
Veteran

May 19, 2010, 7:29 PM

Post #89 of 115 (1617 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

knutnhuny;....

jts1957 is correct....I don't have a lick of experience on LCD , Plasmas Etc....
I suggest you be patient with your thread/post & someone should be along
to try to help you out....
Sorry , I can't.... Unsure

......

jts1957;....

Quote

Your set: Late 2000's LCD display.
No comparison. Totally different technology. Unimpressed

100% correct!!!

Quote

This set: 90's three CRT rear projection.

..100% incorrect !!!....
From post #1;=>..

Quote

i have an rca tv of model g35302wk and it won't turn on.

35" glass CRT type set....

kingm316;....

Next,we go to U1001 (The big IC to the right of the tuner)......
With the set plugged in & OFF , go to pin #23....
Hold your meter lead on that pin & press power one time.....
Read volts.....
Unplug TV & wait or safely discharge 140 vdc....
Plug TV back in....
Go to collector of Q4302 (Horiz Driver Transistor)....
Read volts....
Hold your meter lead on the collector & press power one time.....
Leave it there for a bit & count how many times the volts changes....
Read volts.....
Post all readings.....

See below pix for location of Q4302...
Also , just to the left of Q4302 is T4301....
That is the Driver transformer for Q4401 (Horiz Out Transistor)....
Check & resolder Q4302 & T4301 pin connections....
Check & resolder flyback pin connections also....
Post results....

THANKS.... Laugh

.....

Later....Ron.M.... Cool

.....
Veteran & Retired TV technician

(This post was edited by Ron.M on May 19, 2010, 7:32 PM)

jts1957
Veteran

May 20, 2010, 12:28 AM

Post #90 of 115 (1600 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

Dabnabit! Excuse me while I remove foot from mouth.

Just upset that my customer's (also 35" CRT) has another bad focus/screen assembly.

-------------------------
Location: Far, Far Away

kingm316
User

May 20, 2010, 2:50 AM

Post #91 of 115 (1591 views)
Shortcut

Re: [jts1957] CTC169 Dead set... [In reply to]	Can't Post

i checked pin 23 of u1001 and when i press power it goes to 4.4v
collector of q4302 was 12.8v when plugged in and when i press power it was hard to read but it was like 12.9v dropped to 12.7v then to 12.9 then to 12.8 then it dropped to 0.2v then to 12.9v. thats the best i could remember because it wasn't the same voltage drop when it tried to turn on, it didn't seem the same speed as before, it seemed a little faster maybe.

Ron.M
Veteran

May 20, 2010, 10:37 PM

Post #92 of 115 (1569 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;....

Something's not right here !!!!
Re-do & re-check the volts on the list below.
Note the minor change in proceedure....

"""Next,we go to U1001 (The big IC to the right of the tuner)......
With the set plugged in & OFF , go to pin #23....
>>>> Read volts with TV OFF..<<<<
Hold your meter lead on that pin & press power one time.....
Read volts.....
Unplug TV & wait or safely discharge 140 vdc....
Plug TV back in....
Go to collector of Q4302 (Horiz Driver Transistor)....
Read volts....
Hold your meter lead on the collector & press power one time.....
Leave it there for a bit & count how many times the volts changes....
Read volts.....

After you do the above , unplug & wait OR safely discharge 140 vdc....
Then plug TV back in....
Go to base of Q4302 with TV OFF...
Read volts....
Press power one time only....
Read volts....
Watch voltage changes & post ALL readings....

Quote

it didn't seem the same speed as before, it seemed a little faster maybe.

WHEN BEFORE ????....

THANKS.... Laugh

.....

Later....Ron.M.... Cool

.....
Veteran & Retired TV technician

(This post was edited by Ron.M on May 20, 2010, 10:39 PM)

kingm316
User

May 21, 2010, 1:26 AM

Post #93 of 115 (1562 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

i have a new developement, i am positive it is a good one. i measured pin 23 of u1001 with the tv off and it was 0v i pressed power and it went to 4.6v then to 0v a total of 4 times. i unplugged and discharged the voltage and then plugged back in and measured collector of q4302 and it was 12.76v with it off and when i pressed power it went to 12.6v then 12.8v then 12.6v then 12.8v then 0.5v then 12.8v then 0.5v then 12.7v and stayed.this time i recorded my meter with my cameraphone so i could watch the readings and be sure this time. after that i unplugged and discharged again then plugged back in and put my meter on q4302 base it was 0v i pressed power and it went to 0.7v then down to about 0.2v and then i heard something that sounded like a high voltage charging and then i looked at the screen and it was on. i changed channels up and down and it was working perfectly. i turned it off and waited about an hour and plugged it back in and it came back on, it took about 5 or so seconds after i pushed the button to hear the high voltage sound but it did come back on. is there something else i should check or is it good to go now

kingm316
User

May 21, 2010, 1:53 AM

Post #94 of 115 (1561 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

after i turned it off the last time i left it plugged in and after about 30 minutes of sitting i tried to turn it on again and it came right on without the 5 second delay. i also have hooked up any cable or antenna to it if that matters.

Ron.M
Veteran

May 21, 2010, 8:43 PM

Post #95 of 115 (1554 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;.....
Yikes.....

........There goes my sanity !!!!....

You have ghosts that like to play pranks at your location.....

Did you re-solder T4301 (Horiz Driver Transformer) & T4401 (Flyback) connections ????...
Post answer....

Quote

is there something else i should check or is it good to go now....

Yes, after the set is on for about 15~20 mins put your thumb slowly up against the outside part of the heatsink of Q4101 (Chopper in power supply)....
Do NOT touch ANYTHING else as that heatsink is at HOT AC ground & you WILL get zapped if you do....
Check & see if it is running abnormally hot....
Post results....
Re-check volts at CR4117 & CR4118....
Post results....
When it's working like it is right now , use it as normal.....
Is your pix & sound OK ????
IF it quits , post & I'll reply asap....
If I don't reply quickly , PM me.....
For some reason , I'm NOT getting email notifications as usual....
Sometimes not at all , other times very delayed notice....
Please post ALL requested answers.....

THANKS...... Sly

......

GOOD LUCK.....

Later....Ron.M.... Cool

....
Veteran & Retired TV technician

kingm316
User

May 21, 2010, 9:08 PM

Post #96 of 115 (1550 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

yes, i did resolder t4301 and t4401 connections before i took the measurements from your previous post. when you say to check cr4117 and cr4118, is that check it while it is on or just in standby mode.

Ron.M
Veteran

May 21, 2010, 9:24 PM

Post #97 of 115 (1549 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;.....

Quote

check cr4117 and cr4118, is that check it while it is on or just in standby mode

Good point....Lets get the volts both ways....ON & in standby....

Don't forget the other info I asked for ..... Wink

....

Later....Ron.M.... Cool

.....
Veteran & Retired TV technician

kingm316
User

May 21, 2010, 11:34 PM

Post #98 of 115 (1543 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

its been on about half hour now and i felt q4101 heatsink and it is warm but i can keep my finger on it so i don't think it is too hot. while the tv is turned on cr4118 is 13.6v and cr4117 is 6.2v. i turned it off waited a minute or two and then voltages were cr4118 12.8v and cr4117 6.7v. when i first turned it on there were kinda rainbow type colors all over the screen but i turned the tv of and back on then i heard the degauss relay click and the rainbow colors were gone and now the picture and sound are both great. but after watching if for a while i have noticed near the bottom left corner of the screen there is a green glow about 4 or 5 inches long and about half an inch high. directly above that at the top of the screen is pretty much the same thing but it is blue and i can only really see it when there is a brighter color on it. i don't think that is too much of an issue, i'll see what it does later on. is there anything else to check or is the tv good to go now. i almost forgot but when i first hit the power button today it didn't come on so i pressed it again and it came right on the second time, i had it unplugged all night if that matterts. now after being on and plugged in a while it goes on and off with no problem.

Ron.M
Veteran

May 22, 2010, 1:36 AM

Post #99 of 115 (1539 views)
Shortcut

Re: [kingm316] CTC169 Dead set... [In reply to]	Can't Post

kingm316;.....

Quote

i felt q4101 heatsink and it is warm but i can keep my finger on it so i don't think it is too hot.

Good....That means that Q4101 IS getting the proper amount of drive voltage....

The voltages at CR4117 & CR4118 are OK both on & off.....

The "rainbow type colors" (called a "purity" problem) are from a magnetism that occurs inside the CRT usually from moving the set from one location to another....
The "degaussing" relay & the degaussing thermistor demagnetizes the CRT....

Quote

i have noticed near the bottom left corner of the screen there is a green glow about 4 or 5 inches long and about half an inch high. directly above that at the top of the screen is pretty much the same thing but it is blue

See if this goes away after you use the set for awhile (3~4 days)....

Use the set over the weekend & give me a final reply on Monday...OK.....

Talk to you then.....

Have a GREAT day & weekend..... Laugh

......

Later...Ron.M.... Cool

......
Veteran & Retired TV technician

kingm316
User

May 24, 2010, 12:10 PM

Post #100 of 115 (1530 views)
Shortcut

Re: [Ron.M] CTC169 Dead set... [In reply to]	Can't Post

so i watched the tv all weekend and the picture and sound were almost flawless, but i did notice a couple things like sometimes when i pushed the power button to turn it on or off it acted like i pushed it twice. i think that is just a problem with the button because i didn't notice it happening when i used the remote and also the menu buttons on the tv acted that way too.
i have not seen the green or blue glow on the top or bottom of the screen anymore but now on the left side when there is a brighter color i can see something like a shadow pulling towards the center of the screen. the screen is still behind the shadow but in the bighter area on the left of the screen it looks like a little shadow coming in the screen from the left.
the only other thing i noticed was when there was a really bright color on the screen i could hear a squeeling. the brighter the picture got the higher the squeeling got. it did go away when i turned down the contrast but if i do that it will be too dark to see anything.
i don't know if there is an issue here or not but it is working for the first time in about 2 years and i am very happy for that. if anything sounds like a problem i can try to describe it better for you if you need.

1 2 3 4 5

View All

Print Thread

Search for (options)

- Page loaded in: 0.16 s on (CGI/1.1)