Bulova Crystal Oscillator ???

[AlanBeckett]

Hello everyone,
I'm not sure that this belongs in Test Gear, but equally I don't think it's ordinary Vintage Radio ....
A Friend of mine rescued this from a skip at work, unfortunately with no piece of gear in sight that it might belong to - see attached. I would guess from the markings that it's a 10MHz oscillator, and that the enclosure may well be heated. Beyond that I haven't a clue. I'd like to fire it up but have no idea of the connections.
Anyone come across one before?
Alan

[Dekatron]

Alan,

I found this information: http://www.wbparts.com/rfq/5955-00-402-1878.html , maybe you can find out some more from that.

5955-00-402-1878 Request for Quote Plus Technical Data
Manufacturing Part Numbers under this NSN: 158-0023-00, 158-0023-01, FC100-10-00MC
5955-00-402-1878 NSN Information
NSN FSC NIIN Item Name INC HMIC ESDC CANCELLED NSN
5955-00-402-1878 5955 00-402-1878 OVEN, ELECTRICAL-ELECTRONIC COMPONENTS 41012 N


5955-00-402-1878 Master Cross Reference Data
Mfg. Part Number ISC RNVC RNCC HCC MSDS SADC DAC
158-0023-00 2 9 5
158-0023-01 2 9 5
FC100-10-00MC 2 3


5955-00-402-1878 Characteristics Data
MRC Criteria Characteristic
STYL STYLE DESIGNATOR 5A OCTAL SOCKET
ABKW OVERALL HEIGHT 2.560 INCHES NOMINAL
ADAV OVERALL DIAMETER 1.250 INCHES NOMINAL
AZTK BODY OVERALL HEIGHT 2.000 INCHES NOMINAL
CZEH COMPONENT TYPE AND QUANTITY ACCOMMODATED 1 CRYSTAL
AKNA INCLOSURE TYPE HERMETICALLY SEALED
AYNF MAINTAINED OVEN CAVITY TEMP RATING 100.0 DEG CELSIUS
AYNG MAINTAINED TEMP TOLERANCE RATING -2.0 TO 2.0 DEG CELSIUS
AYNJ HEATER ELEMENT OPERATING VOLTAGE RATING IN VOLTS AND TYPE 6.0 AC MINIMUM AND 117.0 AC MAXIMUM
TTQY TERMINAL TYPE AND QUANTITY 8 PIN

[Skywave]

Originally Posted by Dekatron

Extract:
HEATER ELEMENT OPERATING VOLTAGE RATING IN VOLTS AND TYPE
6.0 AC MINIMUM AND 117.0 AC MAXIMUM

Hmm. One of the photos. that Alan has presented clearly states 115v.a.c. or 230 v.a.c.

I see it is mounted on an Octal plug. How many pins are actually 'available'? By my reckoning, I can think of 6 that could be accounted for:
3 pins for 115v or 230v (assuming one common pin) for the oven;
2 pins for O/P: signal and ground;
1 pin for case.

It's a pity that it is dipped in some sort of goo: otherwise we might be able to work out what the connections are. Nevertheless, a few resistance measurements might tell us something.

Al.

[Dekatron]

The NSN information is not always 100% correct, and sometimes omits some information but it is a good starting point as you usually get some hints on where to look.

Bliley crystal ovens might be another model that can be more or less identical, here's an old datasheet: http://novatech-instr.com/Fun/BlileyTCOSeries.pdf

[Herald1360]

The component visible in picture 4 looks like a standard thermostat switch, which would tie up well with the Bliley part. It's probably just an ovened 10 MHz crystal in which case you could find the crystal connections without damaging anything by perming all possible 2 from 8 pin selections and wrapping a simple Xtal oscillator circuit round them. It looks like the heater should be easy to locate, the thermostat will be closed at room temperature, so just look for a resistor- if it's really a 115V device then it should be around 2.5K for about 5W of heater power.

The other component visible in picture 5 could be just a suppressor cap across the thermostat.

[AlanBeckett]

Gentlemen,
All I can say is fascinating!
Back in the early/mid '70s I designed many ovened crystal modules into equipment, but nothing like this. The ones I used were damned expensive and I'd spend days working out one frequency which would do everything with suitable dividers.
This would appear to be more of a standard unit/frequency.
There are several things that don't match with the above data:-
First, it clearly says 115 VAC 230 VAC, which is way above what's quoted. In fact it would appear to be positively lethal.
Second, it isn't sealed - I didn't break any seals, just slackened the screws and twisted. Incidentally, the screw postions are not symetrical - you are constrained to put it on one way.
Finally, I was disappointed that the Bliley information implies that there is no Standard Configuration.
More research methinks.
Alan

[Dekatron]

Alan,

I hope you will find this website interresting, I just did not find it amongst my links yesterday : http://www.bliley.net/XTAL/ . I can't guarantee that you will find the information you need there but it will hopefully be a lot of interresting facts and information there!

[woodchips]

This looks very similar to a frequency standard used in a radar test set I disintegrated. It was not a crystal but an RC network used in the timing for the IFF pulse, this might be similar? Bob

[ashenlight]

Hi Alan,
I have a piece of very old Tektronix test equipment which has this oscillator fitted.
My own unit has been messed about by a previous owner. Would there be any possibility of purchasing this crystal from you to return it to original shape?

Best regards,
Nigel