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Matthew kane · 23rd Jan 2021, 4:48 am

Thanks for that, looks like my unit went through a service centre here sometime ago as there was a very old looking printed manual stapled into a booklet with some notes in the back schematics section.

Having a quick look inside the board behind the meter, there seems to be a slider based trimmer resistor to I’d assume adjust the resistance the circuit should see from meter similar to how the ‘swamp’ resistor works in the early AVO testers.

The manual also notes there was a later iteration of the 45D called the D2 which had a 3 x multiplier to measure 3 times the transconductance compared to the 2 x multiplier of the normal 45D tester.

Overall very simple circuit and very clean inside my unit. Have started refinishing the panels and disposed of the old AC cable.

Can the two black box styled diodes/half wave rectifiers be replaced with a 1kv/1A modern part, a’la 1N4007 or similar?

23rd Jan 2021, 4:48 am	#3
Matthew kane Tetrode Join Date: May 2019 Location: Melbourne, Victoria, Australia. Posts: 66	Re: Taylor 45D Calibration and Tech Details Thanks for that, looks like my unit went through a service centre here sometime ago as there was a very old looking printed manual stapled into a booklet with some notes in the back schematics section. Having a quick look inside the board behind the meter, there seems to be a slider based trimmer resistor to I’d assume adjust the resistance the circuit should see from meter similar to how the ‘swamp’ resistor works in the early AVO testers. The manual also notes there was a later iteration of the 45D called the D2 which had a 3 x multiplier to measure 3 times the transconductance compared to the 2 x multiplier of the normal 45D tester. Overall very simple circuit and very clean inside my unit. Have started refinishing the panels and disposed of the old AC cable. Can the two black box styled diodes/half wave rectifiers be replaced with a 1kv/1A modern part, a’la 1N4007 or similar?