James Millen 90651 Vacuum Tube Grid Dip Oscillator Meter in Excellent Condition S/N H803

Write a Review

MPN:

90651

Condition:

Used

Shipping:

$16.00 (Fixed Shipping Cost)

Description

Description

James Millen 90651 Vacuum Tube Grid Dip Oscillator Meter in Excellent Condition

This unit is in beautiful condition. This unit was obviously not used much at all.

I discovered there was a break in the AC cord that was not obvious and took me a while to find. It must have been closed in a drawer or something similar.

I fixed the cord and it has a small piece of shrink wrap to cover the repair. The meter now works great and is ready for use.

A first Generation reproduction of the manual is included.

The Millen 90651 is a classic vacuum-tube grid-dip oscillator (GDO, also called grid-dip meter) from James Millen Mfg. Co. (Malden, MA), first released to the public in mid-1949.

It is a versatile RF test instrument used primarily as an oscillating frequency meter to find the resonant frequency of de-energized RF circuits (antennas, tanks, traps, etc.). It can also function as a signal generator, field strength meter, absorption wavemeter, and for measuring inductance/capacitance when paired with known components.

jamesmillensociety.org

Key Specifications

Frequency range: 1.7 to 300 MHz covered in 7 bands via plug-in coils (standard set usually labeled A–G or similar). Optional low-frequency coils extend it down to ~220 kHz.
Power: AC mains (tube-based oscillator, typically requires a power cord).
Features: Drum dial with calibrated scales, plug-in coils stored in a rack or case, often includes a carrying case.

It was a popular and well-regarded instrument among hams and professionals for decades, praised for its stability and build quality in its era.Serial Number H803 and Production ContextJames Millen Society maintains a serial number registry. Your H803 fits in the letter-prefixed series (e.g., they list nearby examples like H679, and later ones like Jxxx, K803, etc.).

jamesmillensociety.org

Production of the 90651 ran for many years (thousands of units), starting in 1949 with low numbers (e.g., #1, #248, etc.) and continuing with letter prefixes in later years/batches.H803 appears to be from the mid-to-late production run of the original 90651 (likely the 1960s)

View AllClose