Full Service Recap PVM and Macs ACT

SONY BVM-2010P service, partial recap and thorough inspection. Interesting model with a pre-BVM 2011 modification for pseudo 16:9 support via Underscan circuit. - Caps changed today (in addition to any prior work by other technician as labelled year 1997)
EA
C37 4.7uf 50v
C35 4.7uf 50v
C33 33uf 50v
C34 33uf 50v

EB
C1 4.7uf 200v (replacement was 250v)
C8 4.7uf 200v (replacement was 250v)
C16 10uf 160v
C12 100uf 25v

PA
C103 33uf 160v

Quality Assurance
- No shorts to ground and polarity checked when checked on replacement capacitors
- CRT raster – basic setup using pull out tray adjustments
- Every daughter board interconnect pins were cleaned with alcohol and lubricated with Deoxit Gold then inserted twice to ‘work it in’
- Tested stable with both built in cross hatch and PAL colour bars via Composite video (ensure a terminator is used on every input please!)
- Infrared temperature monitoring shows appropriate ranges

Another Amiga A1200 motherboard, this time with a bespoke transistor replacement required. Also, the power supply connector itself was part of the problem. See note:
Planning
• Review all communication in FB Messenger, agreed scope of work is high quality recap surface mount
electrolytics for tantalums
• Visual inspection shows corrosion – in contrast to the surrounding logic board that at face value looks like
new.
• Existing caps removed with no damage to surrounding traces or components
• Rosin flux added and soft copper braid used to initially clean off the corroded pads and boil out
• Cleanup with alcohol and cotton, progressing to Safewash 2000 and two stage rinse and drying process
• Pads tinned fresh for replacement capacitors (All quality Fujitsu AVX tantalum)
Soldering and rework
• Conservative heat stress approach – polyimide tape to surrounding components etc
• Replacement capacitors soldered in using tweezers and less than 3 seconds per joint. Gentle pressure
applied centrally to ensure flat positioning on board
• Cleanup of fluxes completed and moved onto testing
Quality assurance measures
• Nil shorts to ground, excessive inspection under high optical magnification
• Photographs taken
• ESD measures maintained throughout including wearing latex gloves
• No-clean flux was cleaned off using appropriate solvent
• Went back on third day to resolder a handful of SMD resistors that needed fresh solder
• Power Supply pins in male jack were black from tarnish, cleaned with fibreglass pen, blown out with air,
then alcohol on cotton bud, then soak in Deoxit Gold then clean pins again.

Vectrex for replacement sound chip with modern replacement (vRetro New Zealand); power supply service and correct vector alignment / centering procedure. Unfortunately about half the photos I took were lost for some reason. So no 'after'..
-Review customer email, noted music off pitch and controller issue likely related to failed sound chip
Soldering
- Existing sound chip carefully desoldered with 0.8mm nozzle and rosin flux, nil issues
- Replacement supplied chip soldered
- Power supply partial recap, comprehensive including linear filter caps (10,000uf) and flyback filters. Selection left as stock to not blow out scope of works.
- Full inspection of power supply board under high optical magnification, multiple passes before and after to resolder suspect dry joints including areas of higher heat stress and flyback transformer pins.

Quality Assurance
- Rubber hot melt to interconnects for strain relief
- Anti corrosion pen and cleaning to pins on CRT neck board, interconnect pins
- No shorts to ground and polarity checked when checked on replacement capacitors
- Alignment using CRT centering rings completed to alignment of crosshair in centre of game overlay
- Cartridge socket cleaned with fibreglass pen, blown with compressed air, cleaned with foam tip and alcohol then lubricated with Deoxit Gold
- Power on switch lubricated with Deoxit F5 and worked in
- Brightness potentiometer lubricated with Dexoit F5
- Tested with customer present, volume

Motherboard ultimately still didn't work but power supply was restored to as new regulation. Apple //e motherboard and matching DynaComp power supply for full service and recap - be sure to look at the high level of physical leakage that I cleaned up with my many processes. Other photos show a perfect job of me removing the stock Apple MT RAM chips - no easy feat to do without damaging anything.

Sharp CZ-600DB CRT Monitor
- Bell and high voltage lead cleaned of thick dust, specialist R14 grease well applied to ultor cap and HV connector checked for proper seating into CRT
- Full inspection of each board under high optical magnification to identify areas of heat stress in solder joints
- Replacement of electrolytic capacitors using ultra high quality replacement parts as sourced from DigiKey USA. See table. All ‘low uF high voltage’ caps replaced along with those either high is ESR or showing heat stress (plastic jacket shrinking back)
- CRT neck pins cleaned with alcohol, then fibreglass pen then recleaned
- CRT front glass cleaned
- Two passes of inspection post reflowing or resoldering of all solder joints as required. Noting prior repair works left mostly untouched, ‘they missed’ quite a few spots
- Further cleaning to ensure work could be completed
- QA pass of replacement capacitors to ensure correct polarity and testing under 110v stepdown.
- Thermal imaging shows acceptable ranges
- Composite video tested and built in UHF tuner displays snow with green OSD
Capacitors replaced:
Capacitor Value Comment
Main board
EA 100uf 160v (most important and physically leaking)
513 1000uf 35v Rubycon PK series
646 10uf 350v Nichicon CS series
644 1000uf 25v
510 470uf 35v

Neck board
831 22uf 250v Rubycon BXE series
839 1uf 250v
857 100uf 25v

Power Supply
707 47uf 160v (was physically damaged)
1501 Value not recorded
709 100uf 16v Upgraded to 25v
501 100uf 6.3v Upgraded to 25v
502 100uf 6.3v Upgraded to 25v