Narrative:

After [takeoff] ZZZ tower notified me on negative transponder signal. I acknowledged and attempted to reset. The tower then gave me a frequency change to [TRACON]. Right after contacting [TRACON] I noticed my back up radio went black. ATC cleared me to climb to 6500 feet and verified my location. Within 30 seconds of conversation with ATC my aspen primary flight instrument went black. I immediately requested to return back to ZZZ and checked and cycled fuses and avionics power after verifying proper volts on the jpi engine monitor. [TRACON] handed me off to ZZZ tower who asked if everything was ok and I responded with instrument failure. They immediately cleared me to enter left pattern for xxl cleared to land number 2. Within seconds of that call my garmin 650 primary radio went black and 30 seconds later I lost my jpi engine monitor. I landed safely on xxl at ZZZ but was unable to transmit 7600 or communicate with tower or ground.

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Original NASA ASRS Text

Title: Bonanza pilot reported a series of equipment malfunctions and returned to departure airport.

Narrative: After [takeoff] ZZZ tower notified me on negative transponder signal. I acknowledged and attempted to reset. The tower then gave me a frequency change to [TRACON]. Right after contacting [TRACON] I noticed my back up radio went black. ATC cleared me to climb to 6500 feet and verified my location. Within 30 seconds of conversation with ATC my Aspen primary flight instrument went black. I immediately requested to return back to ZZZ and checked and cycled fuses and avionics power after verifying proper volts on the JPI engine monitor. [TRACON] handed me off to ZZZ tower who asked if everything was Ok and I responded with instrument failure. They immediately cleared me to enter left pattern for XXL cleared to land number 2. Within seconds of that call my Garmin 650 primary radio went black and 30 seconds later I lost my JPI engine monitor. I landed safely on XXL at ZZZ but was unable to transmit 7600 or communicate with tower or ground.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.