SG503: Difference between revisions
No edit summary |
No edit summary |
||
| Line 35: | Line 35: | ||
* [https://www.youtube.com/watch?v=oRUtsDIOA40 SG503 Lab Check In and Calibration] by Zenwizard Studios @ YouTube | * [https://www.youtube.com/watch?v=oRUtsDIOA40 SG503 Lab Check In and Calibration] by Zenwizard Studios @ YouTube | ||
* [https://www.youtube.com/watch?v=O0E6QeX82LY Tektronix SG503 Refresh and Alignments] by Zenwizard Studios @ YouTube | * [https://www.youtube.com/watch?v=O0E6QeX82LY Tektronix SG503 Refresh and Alignments] by Zenwizard Studios @ YouTube | ||
{{Documents|Link=SG503}} | |||
==Prices== | ==Prices== | ||
| Line 57: | Line 58: | ||
</gallery> | </gallery> | ||
{{ | ==Components== | ||
{{Parts|SG503}} | |||
Revision as of 08:21, 9 October 2023
The Tektronix SG503 is a 250 MHz leveled sinewave generator plug-in for the TM500 system.
It was primarily intended to be used as an oscilloscope calibration device for measuring bandwidths up to 250 MHz. Unlike later instruments like the SG504, it does not use a leveling head but was designed and calibrated with high quality coaxial cable (P/N 012-0482-00) to operate as a closely matched system when terminated into a 50 Ω load.
Nine overlapping ranges cover the frequency band from 250 kHz to 250 MHz, with an additional range reserved for a 50 kHz reference frequency.
The SG503 shows the selected frequency on a 3-digit LED counter.
Key Specifications
| Frequency | 50 kHz, 250 kHz to 250 MHz in nine ranges |
|---|---|
| Frequency accuracy | Within ±0.7 of one count of the least significant displayed digit for the indicated frequency |
| Amplitude | 5 mVp-p to 5.5 Vp-p in three decade ranges (terminated into a 50 Ω load) |
| Harmonics | 2nd harmonic ≥35 dB down from fundamental, 3rd and higher harmonics ≥40 dB down |
Rear interface
The sine output, remote amplitude control input, and a 12-bit non-multiplexed BCD version of the counter value are available via the rear connector.
Internals
The SG503 uses two LC Hartley oscillators, one for 100 MHz and above with an air-core inductor, the other for the lower ranges using switched ferrite-core inductors. Tuning is accomplished via a traditional three-section variable capacitor. After filtering, a regulated power amplifier stage (caution: beryllium oxide in transistor cases!) is followed by a peak-to-peak detector for the amplitude control loop, and switchable output attenuators.
The frequency counter is built from a 10131 ECL prescaler followed by 7490 TTL BCD counters and 7-segment decoders (display not multiplexed).
Notes
The Tek 012-0482-00 cable is made from RG-223 50 Ω double-braid shielded coaxial cable (or equivalent), and is exactly 36" from end-to-end.
Links
- SG503 @ amplifier.cd (German) including measurements of cable influence (1 m Belden H-155 as replacement for original cable)
- SG503 Peak-to-Peak detector substitute by John K. Bennett AE0AM
- SG503 Lab Check In and Calibration by Zenwizard Studios @ YouTube
- Tektronix SG503 Refresh and Alignments by Zenwizard Studios @ YouTube
Documents Referencing SG503
Prices
1979: $1,325 ($5,200 in 2022 Dollars)
According to an internal memo, in 1979 annual sales were estimated at 1200 units.
Pictures
-
Early SG503
-
Early SG503
-
Late SG503
-
Late SG503
-
Late Left Internal
-
Late Right Internal
-
-
-
-
Early SG503 Attenuator Board Part
-
Early SG503 Attenuator Board Top
-
Early SG503 Attenuator Board Bottom
Components
Some Parts Used in the SG503
| Part | Part Number(s) | Class | Description | Used in |
|---|---|---|---|---|
| 151-0614-00 | 151-0614-00 | Discrete component | Tek-made RF power transistor | SG503 |
| 155-0107-00 | 155-0107-00 | Hybrid integrated circuit | leveller | SG503 |