We really can not recommend the Deepace range of vector network analyzers (VNAs). We had one customer who had some success with our coaxial SMA calibration and verification kits on a Deepace KC901V, but the KC901V does not have the required support in firmware to properly support a professional VNA calibration kit. The Deepace firmware can't take into account the fringing capacitance of the open calibration standard, so whilst Kirkby Microwave can give an offset length of the open to partially compensate for this, there's no way to do this well.
A read of the very brief Deepaces manuals indicates to us that the designers are mis-guided about a lot of things related to RF, so we would advise against purchasing a Deepace product. However, we do appreciate they give a lot of functionality, for quite modest cost. Whilst we are not particularly impressed with the Agilent or Keysight N9912A FieldFox, these are certainly better than the Deepace products, and N9912As often be found used on eBay at quite modest prices. If you wish to obtain a used N9912A, get one with plenty of software options, as the options cost a lot if purchased from Keysight. The Keysight N9923A is a much better VNA than the N9912A combination analyzer, but at the time of writing (July 2018), N9923As are still quite expensive on the used market. We have written a few comments about the N9912A on our FieldFox support pages.
Despite our concerns, we have a couple of customers with Deepace VNAs, and we can provide data in a format most suitable for a Deepace product. The KC901V is somewhat better than the KC901S, but we can not recommend either. The KC901S assumes ideal standards, whereas the KC901V does at least allow an offset length to be set for the standards, but this is really not sufficient above a few hundred MHz.
Kirkby Microwave Ltd is registered in England and Wales, company number 08914892. Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT.