Here at Z-Communications, Inc., our experienced team of dedicated professionals ensure that you receive the highest quality of service and support when placing or inquiring about an order.

How do I contact an Applications Engineer?

There are a number of ways you can reach one of our applications experts. You can contact us via our contact page; or call us at (858) 621-2700 between the hours of 9:30 AM – 5:30 PM PST. All questions and comments will be answered in a timely manner. << back to top

How do I solder a VCO onto the PCB?

You can solder a VCO onto a PCB using either of two very simple procedures. The first step is a manual process that is explained in application note 107. You may also use a convection oven to solder the device securely onto the PCB. That process is outlined in application note 112. << back to top

Is it important to load the output to the VCO properly?

Loading the output to the VCO properly is probably the key feature of allowing the VCO to meet the specifications on the data sheet. Application note 102 can delineate the proper process for loading. << back to top

The output power coming out of the VCO seems lower than what Z-Comm has specified. Is that a problem and are there any suggestions?

Often, low output or fluctuations in output power across the frequency band are attributed to a less than optimum output match at the RF terminal of the VCO and/or grounding problems. Ultimately, Z-Communications VCOs are designed to operate with a 1.67:1 VSWR (about 14 dB return loss) and, sometimes, the reactance at the output terminal needs to be investigated. Depending on the VCO, we recommend at least a 6 dB pad (resistive pi-pad network should suffice) of isolation along with a MMIC amplifier. In other words, there should be about 40 dB of reverse isolation. Furthermore, be sure that the VCO sits on a ground plane with a number of plated through holes (vias) spaced between 20 and 30 mils wide. Also, note the presence of soldermask can sometimes degrade VCO performance. Contact our Applications Engineering group for more information. << back to top

I’m designing a modem whose BER increases when the VCO picks up stray perturbations. Any suggestions on how to minimize microphonic pickup?

The VCO is a transducer because any mechanical signals present on the PCB will naturally be picked up by the VCO’s RF shield. One step towards minimizing the effect of microphonics in the loop would be to ensure that the VCO is adequately grounded. Another step would be to utilize polyester composition capacitors in the loop filter and supply lines instead of ceramic composition capacitors. << back to top

Can you supply me with test data on the VCO product I have?

Since each VCO manufactured by Z-Communications, Inc. is tested before it is shipped, you can be assured that it is fully compliant to specifications. Please refer to the data sheets and applications notes. << back to top

Does Z-Communications, Inc. build custom VCOs and PLLs? If so, what information is needed?

Yes, we build custom VCOs and PLLs. Please submit the information requested on our Custom VCOCustom PLL or Custom SFS Series page and someone will contact you shortly after that. << back to top

Can I use several VCOs for multiband switching?

Yes, you can use as many VCOs required to cover your frequency range as long as your design has enough power to drive all VCOs according to specs. For more information please see our application note AN-105. << back to top

Should a Z-Comm VCO work at zero volt tuning voltage?

Yes, all Z-Comm VCOs should operate at zero-volt tuning voltage. << back to top

Will Z-Comm VCOs operate on a higher/lower supply voltage than the one specified?

A VCO will operate at a lower supply voltage, but it will show degradation and inconsistency in power and tuning range. We do not recommend higher supply voltage as it can destroy the components inside. << back to top

Can the shields of an existing VCO be trimmed lower to fit my design?

We may lower most of our shields on CLV series and V series up to .13” and our SMV series up to .08”. The CRO series will only be available in .22” due to its Coaxial Resonator. << back to top