TOF-1 Amplifier Tuning Aid

The TOF-1 amplifier tuning aid is available with most Ameritron and some Drake and Heathkit models in stock. Please be patient for non-stock boards!  This board is compatible with almost all amplifiers that have a ground side grid meter system. A ground side grid meter system is described at this link:

A video is at this link:

This board is not a tuning pulser.  This board allows you to see the real peak grid current in all modes, including SSB voice or when using a tuning pulser. By knowing true grid current, you know if the amplifier is mistuned in a direction that causes flat topping or splattering. It is a running indicator of proper tuning.

All TOFs include a latching relay system that will lock the amplifier out when grid peaks are consistently too high. To correct this you either reduce drive or you open the loading capacitor up (less capacitance). This is a very handy device, especially for other people on the band with you. Without one, you can mistune on carrier and not know your amplifier is flat topping on SSB.

The cost is $99 plus shipping. You have to email me at the order link below and tell me your particular type of amplifier. I will need your address also.

This board features:

1.) Peak reading grid current allowing constant reading of peak grid current. Peak grid current is the single most important indicator of proper drive levels and tuning!

2.) LED warning indicator. Grid current exceeding a predetermined value flashes a bright red warning indicator.

3.) Overload relay. This circuit disables the amplifier at a predetermined grid current. The lockout is reset by momentarily placing the amp on standby.

Please email for availability. Please be patient.    Email Link

Installation Instructions


AL811 Series

AL811 Install (old legacy site)