UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Buffer Amplifier for Digital Frequency Counter

David G4EBT · 19th Apr 2021, 12:47 pm

Two further 'scope pics of the MK1 version, and three pics of the MK2 PCB.
(The circuit and component layout is identical in both versions).

The MK1 PCB was 9cms long x 4.5cms high - the MK2 is 6.5CMs long x 3.5cms high.

Pic 1: MK1: 400mV in, 800mV out at 5 MHz.
Pic 2: MK1: 200mV in, 400mV out at 10 MHz.

Pic 3: Component overlay of the MK2 version(same as MK1, but smaller PCB). Two versions of the MK2 PCB design, one with tracks (not used), the other with blocks on the underside and a ground plane on the top surface of the PCB.
Pic 4: The etched underside of the PCB.
Pic 5: The top ground plane, showing clearance around the non-grounded holes.

Some more pics to follow.

19th Apr 2021, 12:47 pm	#2
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,761	Re: Buffer Amplifier for Digital Frequency Counter Two further 'scope pics of the MK1 version, and three pics of the MK2 PCB. (The circuit and component layout is identical in both versions). The MK1 PCB was 9cms long x 4.5cms high - the MK2 is 6.5CMs long x 3.5cms high. Pic 1: MK1: 400mV in, 800mV out at 5 MHz. Pic 2: MK1: 200mV in, 400mV out at 10 MHz. Pic 3: Component overlay of the MK2 version(same as MK1, but smaller PCB). Two versions of the MK2 PCB design, one with tracks (not used), the other with blocks on the underside and a ground plane on the top surface of the PCB. Pic 4: The etched underside of the PCB. Pic 5: The top ground plane, showing clearance around the non-grounded holes. Some more pics to follow. Attached Thumbnails __________________ David. BVWS Member. G-QRP Club member 1339.