Plans for New FM ATV
Receiver/Transmitter Boards

November 2003

New Receiver

While trying to improve the 13 & 23 cm Comtech receivers and developing the Platinum modifications, I came up with lots of ideas for a better receiver design. Other than the 23 cm transmitter low freq problem, the transmitter and tuner modules themselves provide excellent video quality, but the Comtech receiver audio subcarrier filter and DC restoration circuits are troublesome. Therefore I am planning to develop a receiver board with better circuits, an efficient switching power supply and options for:

• AFT (Auto Fine Tuning)
• Audio Amplifiers for directly driving speakers
• LCD for Frequency, Signal Strength and Supply Voltage Display (for battery powered applications)
• Scanning
• Alarm Output on Video Reception
• 2nd Tuner for a Single Board Dual Band Receiver.
• Companion transmitter board for 1 or 2 transmitter modules for a single board

The concept is for a board that can be built as a basic receiver, like the existing Comtech receiver, or with as many optional features as one desires by simply adding additional components and configuring a few jumpers.

I hope to have something ready to present by spring.

New Transmitter

I want to develop a transmitter board with options for:

• an LCD for Frequency Display
• an ALC (Automatic Level Control) circuit
• 2nd transmitter module for a Single Board Dual Band Transmitter

I also want the option to snap off the PIC and LCD board portion for a receiver plug-on transmitter board for a complete mono-band or dual-band ATV transceiver. Transmitter frequency would be set and displayed via the receiver and its LCD. And for dual-band ATV transceiver configurations the option to cross-band repeat for linking applications.

I also want to try and find an even better solution for the poor 23cm transmitter low freq response problem than the existing Platinum Mod.