RB7501 DDS VFO (c)

(For Use With The Drake TR-7 / R7 In Split Or Tandem Modes Of Operation)

The RB7501 DDS VFO(c) is a high stability oscillator that replaces the Drake TR-7/R-7 PTO. Other models are currently under development. The RB7501 DDS VFO(c) uses a Zilog EZ80F91 processor running at 50 MHz and an Analog Devices AD9851 DDS IC. The unit comes with a universal power adaptor (100 to 240 VAC, 47-63 Hz) and cable for the Drake TR-7 and R-7. For Frequently Asked Questions, click here. This unit also features:

Shaft encoder with 1000 steps/ revolution

Heavy solid aluminum knob for professional feel

Selectable tuning step rates of 1, 10, or 100 Hz/ step (1 kc, 10kc or 100kc/ revolution)

Temperature compensated master crystal oscillator with 2.5 PPM stability

Dual VFO implementation allows transmit and receive on different frequencies within the same band or transceive operation on either of two displayed frequencies (button selectable)

Four line backlit LCD display shows:

Band (1.5 to 30MHz in 500kc bands)

VFO A frequency (transmit frequency in split mode)

VFO B frequency (receive frequency in split mode)

Split or transceive mode

Transmit or receive operation

Tuning step size

Seven push button switches provide:

Selection of Drake PT0's or DDS VFO

Selection of receiver controlled by the RB7501 (TR-7 or R-7)

Use of tuning knob to change bands (4 bands/ revolution) or frequency (1000-steps/ revolution)

Selection of split (separate transmit and receive frequencies) or transceive modes of operation

Selection of VFO A or VFO B for control by tuning knob

Momentary button to transfer content of VFO A to VFO B

Momentary button to transfer content of VFO B to VFO A

Specifications

Operating temperature: 32° -120° F

Frequency stability: 2.5 PPM (+ 1 Hz at constant temperature)

Output frequency: 5.05 - 5.55 MHz

Output voltage: Approximately 1.2 Vp-p across 50 ohms

Size: Approximately 6 5/8"w x 4 1/8"h x 6 Ľ" deep

Power consumption: 6 – 8 watts

Weight: Approximately 2 pounds

Case: Sheet aluminum .063" thick, painted black

Frequency accuracy: + 2.5PPM + accuracy of TR-7 or R-7

Power required: Supplied by Plug-in power supply. 12VDC (regulated) at approximately ˝ A (11.5 to 12.5 VDC).

Disclaimer:

The RB7501 DDS VFO(c) displays calculated TR-7/R-7 frequency to a resolution of 1 Hz. It does not actually measure the TR-7/R-7 transmit / receive frequency but calculates it based on the DDS frequency (assuming that the other oscillators in the radio are correct). If a significant difference exists between the RB7501 DDS VFO(c) frequency and that displayed on the radio, the radio may require realignment.

Price $500 U.S.