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QUESTION NO. P082203-4: Proview 986M monitor FCC IJE986. What are the values of Q663 and Q664? The board is version 200-100-PR98E rev: F3+. |
Q663 and Q664 are shown as being either KSC5042F, or 2SC4686A, in the schematic. Possible alternatives are 2SC4630, or a 2SC3675 with insulator hardware added. B&D Enterprises (ww.bdent.com) is one source for these transistors. |
QUESTION NO. P72303-3: Proview px561 monitor. I need the reference of the transistor Q630 . |
Q630 is IRF634, or an equivalent type. IRF740A can also substitute. If Q630 is bad, also replace C635, and carefully check D632 for reverse leakiness. |
QUESTION NO. P50803-5: Proview pk-986 monitor FCC ije986. I need the value for RT502. |
RT502 is an inrush-current limiter whose ohms rating is about 8 ohms at room temperature. A possible substitute might be a Thermometrics type CL110. |
QUESTION NO. P50203-2: Proview pk-986 monitor FCC ije986. I need the value for R502 and Q502. |
In the schematic for IJE986, Q502 is a 600 Volt, N-channel Mosfet, such as 2SK2141, 2SK2645, STP7NB60, or IRFBC40; (insulator added as required). R502 (47K) is shown in this schematic as being left open (not installed). |
QUESTION NO. P92602-2: Proview Technology 772 (200-100-pr98e) monitor. Original problem was Q502 mosfet, R521, R520, ZD502 burnt or open. Replaced Q502, resisters,18v zener and IC502 KA3842D. No when unit is plugged in a ticking sound can be heard. VCC to IC502 varies from 11vdc to 14vdc the ticking sound is about every half second to second. Checked ac output from transformer T501 secondary and the 55vdc pin 9 is at least 75vac and dc from top of c527 is 2vdc pulses in synchronize with ac pulses from transformer. Keep in mind the set cannot be turned on at unless c527 is removed. If removed too long it will take out next cap in line (C527). I have found a mistake in CKT prints, R605 is not 1.2 k ohms it is actually 10k ohms 5%. What should be the time duration of the ac pulse when the set is just plugged in not turned on? There is no brown glue around FBT or any other ckt. The only glue used is a white silicone type on some components. |
The rapid ticking and voltage cycling suggests an overload or short somewhere, possibly on the 55V supply. Since C527 is on the 55V supply,. Check if D508 is leaky or shorted. Also, Q630 is fed from that supply, so check if Q630 is leaky/shorted, as well. If Q630 is bad, also check L603, and replace D632 and C635. |
QUESTION NO. P91602-7: Proview 770M monitor, changed burned Q630 and number of other components. Picture is too wide and pincushion at maximum (corners further away from center). H-size, pincushion and trapezoid are unadjustable. |
Not sure of board ID number but you will find a feed diode next to flyback towards middle of board standing vertically on a heat sink. It will either be short or leaky. If not check the free standing transistors close by. |
QUESTION NO. P80502-7: Proview PS-560 monitor, FCC IJE-564. Looking for the value of D625. |
The schematic for FCC# IJE-564 shows D625 as 1N4148. |
QUESTION NO. P80702-1: Proview 770m monitor. I need the value of r672 as it is cooked. |
Proview model numbers are ambiguous, but if your unit is FCC# IJE770,then R672 is listed as 39 ohms, 1/2 Watt. |
QUESTION NO. P61302-11: Proview 572 monitor is dead, read short across Horiz. output transister, Q601. |
Replace shorted C635, 22UF@250 volt DC, connects to pin 3 of IFT. |
QUESTION NO. P41802-10: Proview ps508 model 564px monitor FCC ije-564 is dead. Replaced blown C635 (22 mf cap 250v) and shorted D675 with no change. |
Replace all caps with 250v near flyback and check dry sold joint. Resolder flyback and all pf. |
QUESTION NO. P41102-9: Proview 986M monitor, FCC IJE986 will power up ok without signal applied. Once signal cable is connected monitor will shut on and off rapidly. Now will not power up at all, have checked for the usual type of failures and shorts but so far no luck. |
Check D632, C635, Q630, Q65A, and R65B (47 ohm). D632, in some units, is a pair of rectifiers, and D632 may test good when it is not. |
QUESTION NO. P40202-1: Proview PV-850DM monitor, need value of R623, R666, R637 and R634. All burned beyond recognition. |
Proview model numbers are ambiguous, but if the FCC number is IJEPV-564D, I show R623 as 4.7 ohm (fusible); R668 as 150K; R637 as 10K; and R634 as 2K. In that circuit, if these resistors were burned, I would suspect a defective flyback transformer. |
QUESTION NO. P40102-5: Proview 772M monitor. I replaced a burned JFET Q630 (Irf 634) and the monitor works well but it burns again after plugging the cable for the computer. I change the JFET for a equivalent . I checked all caps but all is good. I cannot find the IRF 634a . |
First, IRF634 is a Mosfet, not a JFET. Digikey (www.digikey.com) is one source for IRF's IRF634 (Fairchild's IRF634A is not much different, electrically). You might be able to use IRF740 or IRF740A, if you cannot get IRF634. Besides Q630, also replace the 3-Amp ultrafast diode, D632, and 250-Volt capacitor, C635, regardless of any testing. If there were any ferrite beads on the legs of Q630, be sure to retain them. |
QUESTION NO. P211-9: EMC Proview 768M Monitor FCC 1JEPV-768. I need values for R520, R521 and C520 burnt beyond recognition. |
R520 = 22 ohms, R521 = 47K ohms, C520 = 0.01 uF. |
QUESTION NO. P116-5: EMC aka Proview SA560 (564SA) monitor w/shorted TDA blew R307. Need the value of R307. |
R307 = 10 ohms/ 3 watts. |
QUESTION NO. P829-10: Proview PV-1768P monitor, only ticking sound. Found dead Q601, replaced with BU4522, failed after a few seconds. C603 is o.k. |
Check b+ fet & caps. |
QUESTION NO. P10703-5: Proview PX-986 monitor FCC IJE 986, Horizontal deflection shrinks to about 1/3 width. Returns to full width instantly when case is flexed. No flexing will bring it back. Digital Horizontal width control adjustment doesn't affect width. |
Check 22mf 250volts cap on +B rail. |
QUESTION NO. P37-1: Proview 770 monitor died. No power, no lights, nothing. Fuse is good, cleaned brown glue from flyback area. Has about 150vac on primary of T501 and nothing on secondary. Is this likely the only problem? I need to identify T501 and a source to buy one. Number on Transformer are 730-102-7721 9928 LAE. |
For this type of component, contact Proview; they will sell parts, but have a minimum. EMC/Proview, 800-776-8439, X5712, Reggie Rosca, parts dept. Have on hand all relevant information, model#, serial#, date of manufacture, part location and marking, etc. |
QUESTION NO. P125-1: Proview PV-7221M monitor had ticking sound. I replaced HOT C5150, worked for 24 hours then dead again and HOT shorted out. |
2SC5207A or 2SC5251 are probably better choices for Q615, than 2SC5150, for this 17" Proview, but that change may not solve the immediate problem. Try checking/replacing the solder on the horizontal/vertical yoke connector. Also a good idea to resolder generally, but perhaps focus on the area around IC604. Probably also should replace C629, and check that FET Q621 hasn't gone bad in the interim. |
QUESTION NO. P726-5: Proview PV-772IM monitor will not come up. Low ticking sound. Checked fuse on main board & is good. No picture or on light. |
Did you check the HOT, Q615? Besides the HOT, check FET Q621, and check/replace cap C629 = 22uF/250V/105? it's usually high ESR or dead. This chassis is also known to get this dead/ticking symptom due to that brown conductive glue, in the power supply area and in the flyback area, affecting the circuitry. Scrape away any such glue you find. |
QUESTION NO. P525-6: ProView 768M monitor has a short in damper diode D604. C604 checks good. After installing a new D604 (DMV56) monitor powers up but does not adjust horizontal size from panel. The size is too big. |
See if there is a leaky Darlington transistor Q301 = TIP122, in the horizontal area. |
QUESTION NO. P222-3: Proview PV-850D monitor is dim. Hot went bad, replaced HOT. Had arcing on collector to yoke (red) trace, hair line crack fixed with heavy solder trace. Still have dim problem but sharp image. Voltages and signal seems OK. Could it be the TLS1233 or sub-bright circuit? This picture tube is manufactured by ERS not a Samsung. Is it the tube? |
Bad (dim) CRT's are very common on this chassis. There is some chance the 6.3V supply for the filaments is low. Scrape off any of that brown glue that goes conductive. This manufacturer uses that all over, on the P/S board, CRT board (G2 area?); also check the adjustment pots (sub-bright pot?), as this glue can sometimes seep into a pot and ruin it. The TLS1233 is a Texas Instruments RGB amp IC; if you want to troubleshoot it, get the datasheet at www-s.ti.com/sc/psheets/slvs126c/slvs126c.pdf as a PDF file. |
QUESTION NO. P1216-4: (5) five Proview 772IM monitors FCC IJEPV-772IM with shorted H.O.T. I replaced the transistor (Q615) with the same type 2SC5251, each time. The transistor blows again after 24 to 48 hours of burn-in. I rung the flybacks and yokes, checked for problems in the B+ circuit and checked the ESR on all electrolytic caps. |
Try 2SC5207A instead of 2SC5251; this type can work in PV772IM chassis where the 2SC5251 fails after a couple days. If you need a source, try B&D Enterprises (800-458-6053; www.bdent.com). |
QUESTION NO. P101-10: Proview PV-8500 monitor FCC ID# IJEPV-5640. No picture, no LED and just a ticking sound from the board. |
Some of these have that brown glue that gets conductive with aging, and causes such problems on the main board, so remove any of that you find there. After that, go to standard troubleshooting. Check the 3842 IC's circuitry and the associated switcher FET, and check out the horizontal components (HOT, FBT, CRT, etc). If the CRT is a Samsung tube, check if it is bad first, before investing $$ in a repair. |
QUESTION NO. P727-3: Two Proview pv1564 monitors, totally dead (no light in power on indicator), and the only sound I hear when power on is from the degaussing. B+ is 0V, but there is power on rhe FET in the power supply. |
Is the FET receiving pulses at its gate from the 3842 chip? If not, check or replace the 3842 IC, check any diodes or resistors between pin#6 and the FET's gate, and see that the power supply is providing the proper Vcc voltages to the 3842 at pin#7 (on a scope, at least 16 volts for startup; not dipping below 11 volts while running). If the Vcc voltages are bad, check any resistors, electrolytics, or diodes off of pin#7. If the FET is getting good gate pulses from the 3842 IC after all, does its drain react to the pulses, or is it dead? Also, check to make sure that the current-sense resistor, in line with the FET source, is not open. This model is also known to develop bad CRT's, so if a new CRT would cost too much, check the CRT out first, before going further. |
QUESTION NO. P615-9: Proview PV 564D 15" monitor. You can barely see the screen with the contrast and brightness adjusted to their max. The images on the screen do not appear distorted just very hard to see. |
Bad CRT's are very common on these, esp. if it is a Samsung CRT. If the heaters have a solid 6.3 V, and G1 & G2 aren't too low, then 100 to 1 that it is dim from a bad CRT. Replace it, there's no point in trying to restore bad Samsung CRT's. |
QUESTION NO. P1231-10: I need a cross reference for ic TLS1233N for Proview 14" monitor. |
TLS1233N is a Texas Instruments RGB preamp IC. Its pinout is different from other IC's for this function (like LM1203), and I do not know any cross. If it is a help, Arrow Semiconductor (800-777-2776) does list TLS1233N in its stock, $1.50 each. |