domingo, 19 de mayo de 2013

SARK Plots for SARK-110 preview available

The SARK-110 can be connected to the PC USB port and it is accessible as a mass storage device for functionalities such as for updating the firmware of the device or for the upload of the measurements to the AC6LA ZPlots program for post analysis.

Starting from firmware release v0.7.4 the SARK-110 implements a composite USB device class including the former mass storage class plus a custom USB HID class allowing the remote control of the device. The specification of the HID interface is public and available at Commands Interface (Beta) for anyone wishing to develop its own client software for any of the major OS's.

The SARK Plots is a client application for the SARK-110 for the Windows operating system. This application is aimed to augment the capabilites of the device when a PC is available, for instance when operating it at the shack.

The software is still in development but a preview is available in the SARK Plots section. This preview is functional but there are some program features that are not yet functional and this program has not been extensively tested. The software will be updated periodically so please check for updates.

The SARK Plots provides equivalent features as the available in the device firmware such as Scalar Chart, Polar Chart (similar to the Smith Chart) and the Time Domain Reflectometer mode for cable testing.

The software provides features such as cursor, markers, user defined or automatic ranges, etc. In addition it will be provided advanced features as transmission line measurements, and adding or substracting transmission lines.

The following screenshots show the functionalities of this program:

Scalar Chart


Polar Chart


Time Domain Reflectometer

jueves, 18 de abril de 2013

SARK100 Clones at eBay

Recently I found several SARK-100 clones sold at eBay. The "Mini" units look a nice improvement to the initial hardware design.

Notice that I do not have any link with the manufacturers and sellers and I cannot ensure the performances and provide support for these units.

SARK-110: New firmware release 0.7.4

A new SARK-110 firmware is available in the Firmware area, and includes some enhancements and bug fixes.

One of the most important enhancements is the implementation of a computer control mode through USB custom HID mode, in addition to the existing mass storage functionality. This feature will be used by a client software for Windows PC that it is currently in development.

Besides, the interface specification and basic interface source code, is available at Commands Interface (Beta) to facilitate the integration with client software from third parties.

Regarding the basic measurement features, there are further improvements in the implementation of the OSL calibration algorithm and corrections in the Cable Test Mode, mainly in the presentation of the Step response. In addition, there are some slight changes to the impedance ranges for the Low scale.

It has been added a VSWR audio feedback to the Single Frequency mode. When activated, the analyzer produces beeps of different duration as indication of the VSWR. The audio is produced only for VSWR values between 1.0 and 10.0, and the duration is shorter for the lower values.

Finally there are some enhancements such as new frequency presets, the capability to change the SWR circle in the Smith Chart, and minor changes to the user interface.

The User Manual has been updated for this new firmware release. The new document is available in the Documents area.

domingo, 10 de febrero de 2013

domingo, 6 de enero de 2013

SARK-110: new firmware release 0.7.2

A new release of the SARK-110 firmware and the PC Simulation is available in the Firmware and PC Simulation areas. The changes are described in the Release Notes document.

One important consideration is that from now on, there will be two firmware variants in each release: one limited to 200 Mhz and the other working up to 230 MHz. The reason for this is because migrating to the 230 MHz version requires performing the full calibration process of the unit, therefore it is delivered the 200 MHz variant to upgrade the unit to the new version without the calibration. The firmware files are the following:
Frequency range: 230 MHz.
It is required performing Detector Calibration and OSL calibration when upgrading to this release from versions v0.7.2.a, v0.7.0 or v0.6.5.  Do not upgrade to this version if you don’t have the proper calibration loads
Frequency range: 200 MHz.
No calibration needed when upgrading from versions V0.7.0 or v0.6.5

The implemented changes in this release are improvements in the look and feel of the user interface and the addition of the "Field Mode", intended for field operation, see below some examples:
Field Mode:

Improved menus:
More visible trace in Smith Chart mode: