Instruments
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DIY: AGC disabler for use when aligning vacuum tube radios
A battery powered, adjustable voltage source for locking broadcast receivers’ AGC lines at a certain DC voltage during alignment. Continue reading
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DIY: Digital EM84 “magic eye” replacement
My first attempt at making a digital replica of an indicator tube. Continue reading
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DIY high temperature programmable thermostat
A programmable thermostat/thermometer/thermofuse with K-type thermocouple sensor. Range from 0°C up to 1024°C (depending on sensor). Continue reading
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DIY RF Step Attenuator/Dummy Antenna
A cheap and simple RF attenuator, with 10dB steps from 0 to -40dB, and integrated dummy antenna, for use when aligning old AM radios. Continue reading
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Andonstar AD407 microscope add-ons, part 2: Base, PSU and LED dimmer
Extending the base platform. Making a custom PSU and LED dimmer. Continue reading
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Andonstar AD407 microscope add-ons, part 1: extender and LED ring
Some of the drawbacks of this microscope, and how to fix them. Continue reading
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DIY: Mini turntable strobe
A crystal controlled, USB powered strobe light for turntable speed adjustment, with selector for 50 or 60 Hz strobe discs. Continue reading
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µTracer (uTracer), part 10: Practical use + preliminary verdict
Video demonstration of tracing anode characteristics of an EL84 + some my thoughts about the µTracer so far. Continue reading
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µTracer (uTracer), part 8: Testing the DIY heater supply
Measuring the output voltage accuracy at different load currents. Checking whether the current limiter works as planned. Continue reading
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µTracer (uTracer), part 7: Making a custom heater voltage and current monitor
A measurement and display board which will be mounted on top of the heater PSU board. Continue reading
CATEGORIES
- Devices (53)
- Audio amplifiers (4)
- Broadcast receivers (12)
- Instruments (23)
- Microcontrollers (8)
- Storage (1)
- Televisions (1)
- Tools (9)
- Processes (53)
- 3D printing (10)
- Concepts (4)
- DIY (41)
- Modification (5)
- Recycled parts (3)
- Repairs (3)
- Restoration (8)
- Woodworking (1)
ABOUT ME
Self-taught electronics hobbyist. Collector of Tandberg and other Norwegian broadcast receivers.
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