310: Difference between revisions

{{Oscilloscope Sidebar|

title=Tektronix 310|

image=Tek 310A-crop.jpg|

caption=Tektronix 310, front view|

introduced=1955 |

discontinued=1972 |

summary=4 MHz oscilloscope|

manuals=

* [http://w140.com/tek_310_early.pdf Tektronix 310 Manual (early, PDF)]

* [http://w140.com/tek_310a.pdf Tektronix 310A Manual (PDF)]

* [http://w140.com/tek_310a.djvu Tektronix 310A Manual (DjVu)]

* [http://w140.com/tek_310_rough.pdf Tektronix 310 Manual (rough, PDF)]

* [http://w140.com/tek_fcp/tek_type_310_factory_cal_proc.pdf Tektronix 310 Factory Calibration Procedure (PDF)]

* [http://w140.com/tek_fcp/tek_type_310a_factory_cal_proc.pdf Tektronix 310A Factory Calibration Procedure (PDF)]

* http://bama.edebris.com/manuals/tek/310a/

* [[Media:tek_310a_fcp.pdf|Tektronix 310A Factory Calibration Procedure (PDF, OCR, bad-OCR)]]

The '''Tektronix 310''' is a compact portable oscilloscope [[introduced in 1955]].

It is a 4 MHz single-trace, single-timebase scope with a 3" (7.5 cm) round CRT. 

The [[Hickok]] company produced a clone of the 310 under a US military contract as the [[AN/USM89B]].

{{Spec | Bandwidth | 4 MHz (3.5 MHz below 0.1 V/Div, AC coupled) }}

{{Spec | Rise time | 90 ns (100 ns below 0.1 V/Div, AC coupled) }}

{{Spec | sweep | 0.5 μs/Div to 0.2 s/Div 1-2-5 sequence}}

{{Spec | Deflection | 10 mV/Div to 50 V/Div, 1-2-5 sequence (below 0.1 V/Div only AC coupled) }}

{{Spec | X input | 1.5 V/Div, 500 kHz, 100 kΩ }}

{{Spec | Z input | 20 V_p-p at rear "CRT Cathode" binding post }}

{{Spec | Calibrator | 0.5 V_p-p to 100 V_p-p, 1-2-5 sequence; 1 kHz }}

{{Spec | Power | 175 W }}

The 310 is a tube scope and uses 175 watts, but it does not have a fan.  Therefore, it tends to run hot, particularly when used in a hot environment with still air.  It has a 165 °F (74 °C)  [[thermal cutoff]] switch in series with the primary of the power transformer. For extended use in one place, a tilted fan base, the [[FB310]] (part number 016-012) was available.  The fan base blows air upward through the perforated bottom panel of the 310.

 

== 310A ==

There is also a revised version, the 310A, [[introduced in 1959]].

The 310 uses printed-circuit boards but the 310A returned to ceramic strip construction.   

P2 [[phosphor]] was standard.  P1, P7 and P11 were also available.

''Is this the only time that a Tek design was moved from PCB back to ceramic strip?''

Tek 310 on base.jpg|310 on fan base

Tek 310 front.jpg|310

This is a nearly true pure vacuum-tube scope, but in the power supply there are some silicon rectifiers  

and in the circuit is one germanium point contact diode.

It is sometimes very useful because it contains a 1 kHz calibrator output with up to 100V level combined with a step attenuator.

Early examples of the Tektronix Type 310A used commodity 3WPx CRTs.  At some point in production,

they switched to a Tek-made CRT, part number [[154-366]], which is compatible with the [[3WP2]].

Unlike later Tek instruments, where the incremental model designated by an “A” suffix only occurred with a significant specification or performance enhancement, the original 310 and 310A were essentially identical.  They even shared the same manual and schematics.  The main difference was the wiring construction.   

The original 310 pioneered the use of circuit board construction, rather than the trusted ceramic strip point to point wiring.  The circuit boards were two sided, however plated through hole technology to interconnect the layers had not been invented yet. Rather, all of the holes for component mounting and interconnect contained a rivet  

which was expanded in a press before the components were installed in the board.  The rivets themselves were not soldered to the copper foil traces, and relied on the pressure from the crimp to make contact.  This proved to be extremely unreliable, with many intermittent connections resulting in high warranty- and after-warranty failure.   

The 310A model essentially used the identical circuit design, but returned to the trusted ceramic strip construction method.

During the lifespan of the 310, Tek evolved its color scheme.  The original 310 scopes had a case painted with a blue metallic hammer tone color.  Later units moved to the crinkled “Tek Blue” color still in use today.

The scope cabinet was hinged to allow it to be opened like a book and operated for access to the circuitry for service purposes.  The 310 and 310A were convection cooled, and required free access to air through the cabinet vent holes to avoid overheating.  It contained a thermal cut-out to protect it from damage if the supply of cooling air was inadequate.  The scope has feet on the rear panel to allow it to be operated on the floor with the front panel facing up, but the manual warns against prolonged operation in this orientation.  Shortly after introduction, Tek offered a Fan Base accessory, which the scope would sit on and provide forced air for better cooling.  While the scope had universal primary wiring options, the fan base did not.  Separate models were available for 115 VAC or 230 VAC operation.

Like most old Tektronix devices the mains transformer holds an indefinite(!) warranty, so hold an eye to that.  The device goes away on ebay here often for 30€ to 60€.

Fun on

*But its not quite clear what the "indefinite" means, live long for the device, the first owner, the company (Tek), the universe, or the transformer itself? ;-)

* [http://richardsears.wordpress.com/2011/11/18/tektronix-310a/ Richard Sears: Tektronix 310 and 310A]

* A Tek 310 restoration @ YouTube: [https://www.youtube.com/watch?v=Ef-6Vfx1oiY Part 1] / [https://www.youtube.com/watch?v=6HG49aX_TlM Part 2]

Tek_310A.jpg|310A Front view

310A_right.jpg|310A Right internal

310A_back.jpg|310A Rear view

310 4.jpg|310 model

ANUSM89B_2.jpeg| Sideview AN/USM89B from Hickok

ANUSM89B_3.jpeg| type-plate of AN/USM89B from Hickok

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