547: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
The 547 is a 50MHz scope that takes [[letter-series and 1-series plug-ins]]. | The 547 is a 50MHz scope that takes [[letter-series and 1-series plug-ins]]. | ||
It has two identical timebases and , when used with the 1A1, 1A2, or 1A4, has the ability | It has two identical timebases and , when used with the [[1A1]], [[1A2]], or [[1A4]], has the ability | ||
to display one input with one time scale | to display one input with one time scale | ||
and another input with a different time scale. | and another input with a different time scale. | ||
| Line 13: | Line 13: | ||
A common problem with 547's is the [[hv_transformer|HV transformer]]. Rather than the wax used in older designs, | A common problem with 547's is the [[hv_transformer|HV transformer]]. Rather than the wax used in older designs, | ||
the transformer was potted in a new epoxy resin, which turned out to absorb moisture over time when used in humid | the transformer was potted in a new epoxy resin, which turned out to absorb moisture over time when used in humid | ||
climates. Excessive leakages requires the regulator to drive the 6AU5 input oscillator tube (V800) harder. Eventually, the drive circuit can not supply enough power to keep the supply in regulation. | climates. Excessive leakages requires the regulator to drive the [[6AU5]] input oscillator tube (V800) harder. Eventually, the drive circuit can not supply enough power to keep the supply in regulation. | ||
The usual solution is to scavenge a replacement from another scope. | The usual solution is to scavenge a replacement from another scope. | ||
The 547 has a five-stage BJT vertical amplifier that is fully differential from the plug-in | |||
connector to the CRT vertical deflection plates. There is a single tube in the vertical signal path, | |||
a [[12AT7]] acting as a unity-gain buffer between the plug-in connector and the vertical amplifier. | |||
* [http://bama.edebris.com/manuals/tek/547 Tektronix 547 Manual (DjVu)] | * [http://bama.edebris.com/manuals/tek/547 Tektronix 547 Manual (DjVu)] | ||
Revision as of 22:07, 19 June 2011
The 547 is a 50MHz scope that takes letter-series and 1-series plug-ins. It has two identical timebases and , when used with the 1A1, 1A2, or 1A4, has the ability to display one input with one time scale and another input with a different time scale. The effect is similar to a dual-beam scope assuming that the input signals are repetitive. This "Sweep Switching" feature differentiates the 547 from the 546.
Triggering is done with tunnel diodes, which tend to shift in characteristics as the instrument ages.
A replacement CRT for the 547 can be taken from a 543B, 544, 545B, 546, or another 547. A common problem with 547's is the HV transformer. Rather than the wax used in older designs, the transformer was potted in a new epoxy resin, which turned out to absorb moisture over time when used in humid climates. Excessive leakages requires the regulator to drive the 6AU5 input oscillator tube (V800) harder. Eventually, the drive circuit can not supply enough power to keep the supply in regulation. The usual solution is to scavenge a replacement from another scope.
The 547 has a five-stage BJT vertical amplifier that is fully differential from the plug-in connector to the CRT vertical deflection plates. There is a single tube in the vertical signal path, a 12AT7 acting as a unity-gain buffer between the plug-in connector and the vertical amplifier.
-
Front view
-
Vertical amplifier
-
Trigger A
