FG504

The Tektronix FG504 is a 40 MHz function generator plug-in for the TM500 system.

Tektronix FG504
40 MHz function generator Tektronix FG504 Produced from 1976 to 1993 Manuals FG504 Instruction Manual (1977) FG504 Instruction Manual (SN B0400000+) (OCR) (All manuals in PDF format unless noted otherwise)

Manuals – Specifications – Links – Pictures

Key Specifications

Frequency range	Sine, Triangle and Square – 0.001 Hz to 40 MHz; Ramps, Pulses or asymmetric waveforms – 0.001 Hz to 4 MHz
Duty cycle	7% to 93%
Output amplitude	30 V_p-p (OC), 15 V_p-p (50 Ω)
Output attenuator	0 to 50 dB in 10 dB steps
DC offset	±7.5 V (OC), ±3.75 V (50 Ω)
Distortion	≤ 0.5% from 20 Hz to 40 kHz
Rise/fall time	6 ns (fixed), 10 ns to 100 ms in 7 steps + variable control
Sweep	1000:1 (500:1 on 10⁶ mult.)
AM input	10 V_p-p for 100%

Links

Tek FG5010 FG507 FG504 Description

Documents Referencing FG504

Document	Class	Title	Authors	Year	Links
070-2088-01.pdf	Book	TM500 Series Rear Interface Data Book		1976	AF501 • AM501 • AM502 • AM511 • DC501 • DC502 • DC503 • DC504 • DC505 • DC505A • DD501 • DM501 • DM502 • FG501 • FG502 • FG503 • FG504 • LA501 • MR501 • PG501 • PG502 • PG505 • PG506 • PG508 • PS501 • PS502 • PS503 • PS503A • PS505 • RG501 • SC501 • SC502 • SG502 • SG503 • SG504 • SW503 • TG501 • TR501 • TR502
Tekscope 1976 V8 N1.pdf	Article	New Products		1976	FG504 • SG504 • Lab Cart Model 3 • SW503 • C-5A
Tekscope 1976 V8 N2.pdf	Article	The FG504 - A New Standard in Function Generators	Ira Pollock	1976	FG504
Tekscope 1977 V9 N2.pdf	Article	Measuring Harmonic Distortion with a Spectrum Analyzer	Ken Matheson	1977	FG504 • 7L5 • 5L4N
Tekscope 1978 V10 N2.pdf	Article	Pulse Generator or Function Generator - Making an Intelligent Choice	Bill Rasnake	1978	FG504 • PG508
070-2088-04.pdf	Book	TM500 Series Rear Interface Data Book		1985	AA501 • AF501 • AM501 • AM502 • AM503 • AM511 • DC501 • DC502 • DC503 • DC503A • DC504 • DC505 • DC505A • DC508 • DC508A • DC509 • DC510 • DC5009 • DC5010 • DD501 • DL502 • DM501 • DM501A • DM502 • DM502A • DM505 • DM5010 • FG501 • FG501A • FG502 • FG503 • FG504 • FG507 • FG5010 • LA501 • LA501W • WR501 • MR501 • PG501 • PG502 • PG505 • PG506 • PG507 • PG508 • PS501 • PS502 • PS503 • PS503A • PS505 • PS5010 • RG501 • SC501 • SC502 • SC503 • SC504 • SG502 • SG503 • SG504 • SG505 • SW503 • TG501 • TR501 • TR502 • MI5010 • MX5010 • SI5010

Rear Interface

Right (as seen from the front, main board)

Pin	Signal
28A	Output (via 30 kΩ)
27A	Output Common

Left (mechanically floating interface board)

Pin	Signal	Pin	Signal
28B	Trig Output Common	27A	nc
27B	Trig Output	27A	GND
26B	Phase Lock Error Voltage	26A	Sweep Reset Output
25B	Trig/Gate Common	25A	Linear Sweep Output
24B	Trig/Gate Input	24A	nc

23B	nc	23A	AM Input
22B	VCF Input Common	22A	Sweep Trigger Input
21B	VCF Input	21A	nc

Internals

The FG504 takes +/– 33 V from the right slot to create a +/– 15 V supply, and the + 11.5 V for a +5 V supply. It uses the 25 V_AC windings, 17.5 V_AC, and + 11.5 V on the left slot for a +/– 25 V supply to the output amplifier. The regulators incorporate the mainframe pass transistors on both slots.

U770 is a 155-0032-00 below S/N B057720, a 155-0217-00 from B057720 on.

Pictures

External

FG504 front panel
FG504 in mainframe
FG504 and PS503A in TM504
FG504 in TM502A
FG504 in TM502A

Internal

FG504 without covers
Main board - output amplifier, attenuator, rise/fall time switch
Detail of output amplifier. Trimmer capacitors for high frequency compensation.
Detail of 50 Ω attenuator. Divider networks (under the ceramic chips) are switched in or bypassed by cam switches. The 0.3 amp output fuse can also be seen.
Ceramic 10 dB divider lifted to show resistor network. Laser trimming marks can be seen.
Function generator board that synthesizes the triangle and sine out of a square wave
Timer board
Circuit detail
FG504 left internal
FG504 left internal upside down
FG504 right internal upside down
FG504 right internal

Operation

Sine out
Square out
Triangle out

Schematics and Locations

A1 Main Board Test Point Locations
A2 Function Board Test Point Locations
FG504 A3 Loop Board Test Point Locations

Components

Some Parts Used in the FG504

Part	Part Number(s)	Class	Description	Used in
155-0032-00	155-0032-00 • 155-0032-01	Monolithic integrated circuit	variable-gain transconductance amplifier (voltage in, current out)	335 • 464 • 465 • 465B • 466 • 475 • 475A • 475M • 634 • 650 • 651 • 652 • 653 • 655 • 656 • 670 • 671 • 7A12 • 475 • FG504 • 1440 • 1460 • 1480 • 1481 • 1482 • 1485
155-0217-00	155-0216-00 • 155-0217-00	Monolithic integrated circuit	variable-gain transconductance amplifier	335 • 475 • 7D20 • FG504
CA3046	156-0048-00	Monolithic integrated circuit	transistor array	4601 • 7104 • 7403N • 7503 • 7B53A • 7D12 • DM502 • FG504 • S-52 • Telequipment D34 • 7603 • 7613 • 7623 • 7633 • FG507 • Keithley 227