Monday 20th May 2024 -


Total Frequency Control News ....

Glass enclosure for quartz crystals - February 2012

Throught their Canadian subsidiary, Laptech Precision. Inc., TFC have released an enhanced version of the MIL spec. HC-26/U glass encapsulated quartz crystal and are the only remaining manufacturer worldwide to provide this ultra clean enclosure.

New clean room facilities have improved the performance for this product which is available up to 220MHz.Glass enclosures are similar in size to the familiar HC-43/U Cold Weld metal enclosure with an identical lead pitch and for precision SC cut resonators both are vacuum sealed. Compared to the metal enclosure the HC-26/U glass enclosure has a number of unique advantages:

-Very low magnetic signature -Insensitive to barometric pressure changes
-Laser frequency trimmable after seal
-Suitable for SC Cut crystals
-Inherently non conducting and insulated from adjacent components
-The HC26/U is the only package that allows easy visual inspection of the workmanship level.

The HC26/U enclosure is sealed by heat fusing the glass envelope to the glass base whilst under vacuum; this is accomplished by the R.F. induction heating of an embedded Kovar ring forming part of the base construction.

The result is a hermetically sealed crystal with very high reliability due to the high temperature seal and the purity of the materials involved. Unlike plated metal enclosures, that have the possibility of outgassing from pores in the plating material, glass is inherently stable and impermeable. This combined with a higher heat tolerance, helps the burn in process to quickly stabilize crystal aging.

This product is suitable for the highest quality r.f. systems, the manufacture of precision OCXO oscillators and high temperature applications requiring the lowest ageing rates.

Specific features include: 

 Package: all glass (13.46 x 10.40 x 4.10)mm
Lead pitch 4.90mm High vacuum seal
Frequency range (4 ~ 220)MHz
Operating temperature range (-40 ~ 200) Deg C

Laptech supply a complete range of precision crystals from 32.768kHz ~ 450MHz complimented by a range of oscillator modules from 1MGz ~ 2.4GHz including TCXO, VCXO, PLL and GPS modules.

Full data sheet at

About Laptech Precision Inc.

Founded in 1972, the company, which is located in a 15,000 square foot facility in Ontario Canada, employs highly skilled personnel, its unique blend of products and services include precision quartz resonators supplied to oscillator manufacturers worldwide, quartz and alloy material fabrication to exacting parallel and optical polish standards and high precision OCXO, TCXO and VCXO oscillators manufactured by the parent company. Additionally a range of miniature smd oscillators purchased from qualified sources are provided to augment the group manufactured products. The company is ISO9001:2008 and RoHS compliant and follows a programme of environmental management


Febraury 2012


Other News Items


TFC’s Flexible, Reliable, Affordable, custom frequency oscillators

TFC’s high quality, miniature ceramic smd, crystal clock oscillator manufactured over the wide ... more

One Stop SMD Power Inductors at TFC

TFC’s comprehensive range of SMD power inductors have an inductance value from 1uH to 1500uH ... more