Modding a 1986 ZX Spectrum +2 (the gray transitional model made by Amstrad and rushed for holidays), with a nasty hum problem coming from the tape deck.

Mods and fixes done: -T4, T5 and T7 reversal (ie old PCB design not meant for 2N3904) -AV out mod: LK6 (vertical sync) changover to LK7 (audio) on pin 3, making it possible to use the DIN port as a RGB+comp sync+audio (for EuroSCART enabled TVs) using a 8-pin DIN connector, or a very simple composite video+audio out using a 3-pin DIN connector -signal modulation mod: move C31 to the composite video encoder's output -tape deck amplifier power cutoff mod (the Keritech version with no reed relay) which stops the horrible hum when tape is not in use -AV cable mod for EuroSCART (Peritel) with audio on DIN connector, freeing up the 3.5mm jack -full electrolytic cap replacement

0:00 Intro 3:33 Initial Test 4:36 Disassembly 10:25 Transistor Reversal Fix 26:08 A/V Jumper Mod 28:48 Power-Up Test 38:48 A Mistake? 40:05 Introducing the Test Gear Cam 42:05 A/V Cable Mod 49:37 The Silent Part 52:55 Still Not There! 54:04 Camera Died, Mike Died, Lost Footage 1:01:19 Let's Play Global Thermonuclear War!

Cleaning the holes with a syringe needle... Powered desoldering gun is so much better, but I don't have one. This video was a pain to make, bench cam freezing and mike going silent. Will follow up with a more in-depth explanation of mods, schematics etc.

At one point all audio disappeared but the video footage was good... Then the cam feed froze again. 54:04 shows missing screw fix and re-assembly. Have a listen to the music project I once participated in!

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