Featuring Fine Vintage and Modern Amateur Radio Gear For Sale

James Millen 90651 Vacuum Tube Grid Dip Oscillator Meter in Good Condition S/N 5101

Write a Review
MPN:
90651
Condition:
Used
Shipping:
$16.00 (Fixed Shipping Cost)
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
  • Discover the classic James Millen 90651 grid dip meter in GOOD condition with full factory coil set and original plastic carry case. Serial 5101 vacuum tube GDO covers 1.7-300 MHz for antenna tuning, resonance checks, and more. Ideal vintage ham radio test instrument
$34.99
Frequently bought together:

Description

James Millen 90651 Vacuum Tube Grid Dip Oscillator Meter in Good Condition S/N 5101 with Full Coil Set.

 This unit is in good condition and appers to be working. This unit was obviously used as it shows some wear.

 The plastic carry case has a small hole in it and the handle on top is missing.

 The meter powers up and has had the main electrolytic capacitor replaced with new modern ones.

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 5101 and Production ContextJames Millen Society maintains a serial number registry. Your 5101 fits in the  series
  • 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.5101 appears to be from the mid-to-late production run of the original 90651 (likely the 1960s)

 

View AllClose

Related Products