Resolutions and Analysis:

Coaxial connector manufacturers Huber+Suhner and Radiall were the first to begin research & development on the Quick-lock connectors. In the past few years, they have successively released QMA (Quick Lock SMA) and QN (Quick Lock N)connectors, and together with Amphenol RF and Rosenberger established the QLF(Quick Lock Formula) alliance so as to share technology, unify quick lock connector interface standards, and profit from joint marketing. Presently, QLF’s versions of QMA and QN are the most widely used on the market.

In the following analysis and comparison of these QLF connector designs, it is shown how new design ideas were reached.

QMA connector:

Below is the design for QLF’s version of QMA (Figure 2).

Testing shows this design to be fundamentally sound, as it can approach SMA’s relatively high electrical performance. However, small problems still exist.

The spring-lock in the QMA connector’s design requires the use of beryllium copper. This mineral is in itself expensive, add to which the difficulty there is in machine processing and its need for thermal processing as well as environmental protection treatment and the overall cost becomes very high.

When the QMA male and female are mated, the effective contact length of the inner conductor is too short, being only 1.60 mm, whereas the effective contact length of the original SMA is 2.30 mm (See figure 1). After several uses, this may result in the reduced contact reliability of the inner conductor.

These there areas are the main respects in which QLF’s version of QMA can be improved upon, and in fact have been in a new version of QMA (hereafter referred to as Anoison QMA, See figure 3), which has been on the market for almost two years, and successfully resolves all these problems.

Anoison QMA’s waterproof seal is cleverly designed so that when under pressure from the outer bevel of the female, an O-ring rests in the groove of the male outer conductor creating an excellent seal and anti-shock effect.

In the Anoison QMA design, the S/S spring-lock in the plug, costs only 1/10 of the spring-lock made from beryllium copper in QLF's QMA, and consists of a ring-like locking sheet with inner and outer teeth. A trapezoid cross section which has an upslope, flat top and down slope is located on the surface of the socket connector’s outer conductor. Thus, when connecting,the inner teeth reach their maximum flexural deformation while rising along the upslope to the flat top, then while moving along the flat top the deformed inner teeth are gradually restored to their original state in the tangential direction of the down slope before finally stopping at the down slope, or at the juncture of the down slope and a flat valley. The external faces of the inner teeth thrust the down slope in its original direction,creating close contact between the contact surfaces with zero clearance and a relatively strong axial force (The axial force greatly influences the performance of passive inter-modulation).In addition, the adjacent inner teeth of the ring-like locking sheet have different lengths,which enable them to stop on different circumferences of the down slope when locking. The angle between the longer teeth and the down slope is ≥90, while that between the shorter teeth and the down slope is ≤90 (See Figure 5). This design creates very good retention force and has excellent anti-shock performance, fully meeting all requirements for military use. In addition, the effective mating cycles of Anoison QMA is over 200 times.

In the interest of improved reliability, the effective contact length of the original SMA inner conductor, 2.30 mm, ought to be maintained, and is matched in the Anoison QMA design.

Two further notes:

The Anoison QMA plug is completely backward compatible with the QLF's QMA jack. In addition, for the purpose of saving space and material, a mini-version of QMA (hereafter referred to as Mini-QMA, see figure 6) has been designed; which combines comparable performance with reduced volume.

QN connector:

As a matter of fact, as early the 1980s, Chinese RF engineers had already developed a Quick Lock Connector based on the N connector’s design (See Figure 7). This connector performed well, especially when applied in special circumstances.

The following are three versions of QN that were released successively by QLF founder Huber+Suhner beginning in 2002. 1) 2002 version (See Figure 8).

QLF’s 2002 version was the first to successfully convert the N type connector’s original threaded connection to a snap-fastening, self-locking one Advantages:

Disadvantages:

2) 2003 version (See Figure 9)

The 2003 version of QN made improvements based on the 2002 design. Advantages:

Disadvantages:

3) 2004 version (see Figure 10).

In the 2004 version, further improvements were made based on the 2003 design.

Advantages:

Disadvantages:

More details please view ANOISON ELECTRONICS.

QMA_AND_QN (last edited 2011-10-19 20:34:36 by 180)