GrahamH's photos with the keyword: band

A pocket personal portable AM (no FM at that time) radio which I built in a 36 exp slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was adequate for primary coverage areas. See Notes on 005.

A pocket personal portable AM (no FM at that time) radio which I built in a 36 exp slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was adequate for primary coverage areas. See Notes on 005.

A pocket personal portable AM (no FM at that time) radio which I built in a 36 exp slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was adequate for primary coverage areas. See Notes on 005.

A pocket personal portable AM (no FM at that time) radio which I built in a 36 exp Kodak slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was adequate for primary coverage areas. See Notes on 005. An oldie added to kick off the Macgyverering group. Using a 36 exp Kodak slide box as a radio case.

A pocket personal portable AM (no FM at that time) radio which I built in a 36 exp slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was adequate for primary coverage areas. See Notes on 005.

A pocket personal portable AM (no FM at that time) radio which I built in a Kodak 36 exp slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was good for primary coverage areas.

A pocket personal portable AM (no FM at that time) radio which I built in a 36 exp slide box at the start of the 68/69 Christmas school holidays. It was originally built breadboard style with a valve-style tuning capacitor. The circuit has three transistors. The signal path flows from the ferrite rod to the first transistor for RF amplification with regeneration. A diode demodulates the signal which is sent back to the first transistor reflexed as the first AF stage. Two more transistors cascaded give more AF gain. A high impedance crystal earpiece couples the audio to the Listener. Performance was adequate for primary coverage areas. See Notes on 005.