RESNET 3.3 Shareware Manual Notor Research 1548 Arata Court San Jose, CA 95125 COPYRIGHT INFORMATION This manual is Copyright (c) John Notor, 1993,1994, All Rights Reserved. ASP OMBUDSMAN POLICY "This program is produced by a member of the Association of Shareware Professionals (ASP). ASP wants to make sure that the shareware principle works for you. If you are unable to resolve a shareware-related problem with an ASP member by contacting the member directly, ASP may be able to help. The ASP Ombudsman can help you resolve a dispute or problem with an ASP member, but does not provide technical support for members' products. Please write to the ASP Ombudsman at 545 Grover Road, Muskegon, MI 49442-9427 USA, FAX 616-788-2765 or send a CompuServe message via CompuServe Mail to ASP Ombudsman 70007,3536." DISCLAIMER AGREEMENT AND SHAREWARE EVALUATION LICENSE Users of RESNET must accept the following disclaimer of warranty: RESNET is supplied as is. The author disclaims all warranties, expressed or implied, including, without limitation, the warranties of merchantability and of fitness for any purpose. The author assumes no liability for damages, direct or consequential, which may result from the use of RESNET. RESNET is a shareware program and is provided at no charge to the user for EVALUATION ONLY. Feel free to share it with your friends, but please do not give it away altered or as part of another system. If you like the program and want to make it a permanent part of your software toolbox, you must register to obtain the right to continue to use the program. You are temporarily licensed to use this shareware version of RESNET for an evaluation period not to exceed 30 days from the date you received this copy. After this evaluation period, you must register to continue to legally use RESNET (see the section called REGISTRATION below for details). Continued use without payment of the registration fee is a violation of the copyright laws and subject to prosecution. When you pay a single user registration fee, you will have full legal rights to the continued use of one copy of RESNET. This single user licensed copy may be used by any number of people and may be freely moved from one computer location to another, so long as there is no possibility that it will be used at more than one location at the same time. If you need multiple copies of RESNET, contact Notor Research to obtain a site license. Site licensing offers a low cost way to license multiple users within a business, or other organization. Commercial users of RESNET must register and pay for their copies of RESNET within 15 days of first use or their license is withdrawn. Anyone distributing RESNET for any kind of remuneration must first contact NOTOR RESEARCH at the address below for authorization. This authorization is automatically granted to ASP vendor and BBS members in good standing. Contact Notor Research to receive the latest version of RESNET. You are encouraged to pass a copy of RESNET along to your friends for evaluation. Please encourage them to register their copy if they find RESNET useful. DEFINITION OF SHAREWARE Shareware distribution gives users a chance to try software before buying it. If you try a shareware program and continue using it, you are expected to register. Individual programs differ on details_some request registration while others require it, some specify a maximum trial period. With registration, you get anything from the simple right to continue using the software to an updated program with printed manual. Copyright laws apply to both shareware and commercial software, and the copyright holder retains all rights, with a few specific exceptions as stated below. Shareware authors are accomplished programmers, just like commercial authors, and the programs are of comparable quality. (In both cases, there are good programs and bad ones!) The main difference is in the method of distribution. The author specifically grants the right to copy and distribute the software, either to all and sundry or to a specific group. For example, some authors require written permission before a commercial disk vendor may copy their shareware. Shareware is a distribution method, not a type of software. You undoubtedly want to find software that suits your needs and pocketbook. The shareware approach makes fitting your needs easier, because you can try before you buy. And because the overhead for the author is low, prices are low also. Shareware is the ultimate in a satisfaction guaranteed product_if you don't use the product, you don't pay for it. REGISTRATION When you register RESNET, you become a licensed user of the program, entitling you to: 1. a minimum of 3 months free support via phone, FAX, CompuServe Information Service email, America Online email, or Internet email 2. a copy of the latest version of the program 3. a printed manual. In addition, you will be entitled to upgrade discounts on new releases of RESNET, as well as discounts on new software releases. To register RESNET, send $19.95 + $3.00 shipping and handling to: Notor Research 1548 Arata Court San Jose, CA 95125 California residents must include applicable sales tax. For your convenience, we have included the file REGISTER.TXT with this version of RESNET. You may print the file and fill it out by hand, or you may fill it out using a text editor or word processing program. If you are a Microsoft Windows user, we recommend you register using the REGISTER.WRI file, and the Windows Write editor. As an alternative, you may print the registration form by starting RESNET and pressing as indicated by the registration reminder screen. If you have questions or comments about RESNET, you can contact Notor Research by phone or FAX at (408) 947-7232 [for FAX, press SEND when you here the phone ring, don't wait for FAX signals], or by sending CompuServe email to John Notor, 75075,467, or America Online mail to JNOTOR, or sending mail via Internet to jnotor@aol.com. ABOUT RESNET INTRODUCTION: RESNET provides you with a simple way to design common resistor networks like voltage dividers and attenuators. With RESNET you supply the desired results and the program takes care of the analysis. For example, a voltage divider network design is as simple as entering the voltages and the bias current, and your done. RESNET eliminates the need for a lookup table when you want tight tolerance components. You select the tolerance and the program does the lookup. And, for those occasions when the exact value is what you want, select the EXACT tolerance option, and you've got it. A must for attenuator design, RESNET offers a variety of styles for the exact configuration you need for your project. Included in this version of RESNET is support for Pi and T single-ended attenuators, O and H balanced attenuators, and, for resistive matching applications, the minimum loss pad. You may specify the terminating impedances separately for those circuits which have unequal source and load impedances. RESNET automatically calculates either the exact resistor values or the closest standard resistor value according to the tolerance you specify, an especially handy feature in those cases where you may be using 1% or tighter tolerances. The program includes the following tolerance options: exact, 0.1%, 0.2%, 0.5%, 1%, 2%, 5%, and 10%. Included with RESNET is a Standard Resistor Value Calculator, a useful tool in general circuit design to convert calculated resistor values to standard values. The calculator displays standard values for all the above mentioned tolerances simultaneously and covers resistor values from 1 Ohm through 10 MOhms. For your convenience, RESNET saves your last set-up configuration when you exit the program. HARDWARE REQUIREMENTS: RESNET requires an IBM-PC, XT, AT or compatible running DOS v2.0 or higher, with 256K of memory, and a monochrome, CGA, EGA, VGA, or Hercules compatible display card. The program may be run either from a floppy disk or harddisk drive. RESNET will run as a DOS program under Windows 3.1. GETTING STARTED WITH RESNET: When you start RESNET the first time, the program asks: Do you have a color monitor [Y/N]? Type Y if you have a color monitor, N if you don't. After you respond, RESNET creates a file called RESNET3.OPT on the default drive which includes the program start-up options. As you use RESNET and then exit the program, the RESNET3.OPT file is updated with the current option settings. Any OPTIONS selections which you made become the default settings when you next use RESNET. If you have not registered RESNET, the next screen will be a registration reminder screen. Press to print a registration form, or to continue. Next the opening screen is displayed. The opening screen shows: 1. the default network selection (the Pi Attenuator, if the program is being loaded for the first time, or the last network you selected if you have been designing with another network style); 2. the data entry boxes, which allow you to set the network design parameters; 3. the default resistor value tolerance (1% if you are loading the program for the first time, or the last tolerance value you selected - the tolerance selection identifies the set of standard resistor values used in calculating the resistor values; 4. the function key command line. FUNCTION KEY OPERATION: F2-Style: F2 selects the resistor network type: Pi, T, Min Loss Pad, O and H balanced attenuators are the available, as well as Minimum Loss Pad, Resistor Divider and a Voltage Divider networks. Pressing F2 repeatedly scrolls through the network styles until you find the one you wish to use. F3-Options: F3 displays a group of options: Rcalc, Tolerance, and Colors; to select one of the options use the up or down arrow keys and then hit the ENTER key, or just type the first letter of the option name. Pressing exits the options window. Rcalc is a built-in standard resistor value calculator, which displays the nearest standard commercial values in 0.1% through 10% tolerances to the value you enter. Rcalc also displays the equivalent noise voltage of the exact resistor value you enter. This handy utility will keep you from rummaging through catalogs and miscellaneous pieces of paper when you need to find the closest commercially available value for a resistor. Press the key to exit Rcalc. Tolerance displays a list of standard value tolerances. Select the one that you would like to use in calculating attenuator values by using the arrow keys. Press ENTER to complete your selection. Pressing exits with no change. Colors displays a list of screen color suites. Pick the one that suits you best by using the arrow keys. Press ENTER to complete the selection and change the display color, or just type the first letter of the selection you would like. exits with no change. F5-Quit: Pressing F5 saves the current options and style selections and exits the program. DESIGNING WITH RESNET Pi, T, O, and H Style Attenuators Entering and editing data for RESNET attenuators involves defining the input and output impedances (in Ohms) and the attenuator Loss in dB. First select the attenuator style you would like to use with the F2 key. Then, using the arrow keys, move the cursor to the input impedance (Ri) data cell and type in the new value. Note: do not press yet. Pressing the key causes RESNET to calculate new resistor values based on the currently displayed data. Now move the cursor to the output impedance (Ro) data cell and enter the new value. Finally, move the cursor to the Loss cell and enter the new value. For any attenuator loss value, there are ratios of input to output impedance that are mathematically invalid. RESNET checks for the validity of the values of Ro and Ri before completing the calculation. If your design specifies a value of Ro not equal to the value of Ri, the Loss value of the attenuator must be a certain minimum value. If this criterion is not met by the displayed data at the time you press the key, RESNET will beep and display the following message: ***Loss value must be at least xx dB *** where, instead of 'xx', an actual value will be displayed. Decreasing the larger value of Ro or Ri, increasing the smaller value of Ro or Ri, or increasing the value of the attenuator loss will allow a valid calculation. Note that the Minimum Loss Pad is a good choice if the attenuator is primarily intended to resistively match impedances. The Minimum Loss Pad calculator displays the loss in dB based on your design data. As it turns out, the Loss value for a Minimum Loss Pad for any valid value of Ro and Ri is exactly the minimum value of loss for any attenuator style with the same values of Ro and Ri. Notice that as you enter data, the cell editor clears the current value, except for the decimal point, when the first key you press is a number key. If you only wish to change a single digit of any cell value, use the arrow keys to select the digit, delete it and then enter the new value. Alternatively, if you press the key, the cell editor will allow you to type over any digit. If you start to edit the wrong cell, press the key and the data will be restored to the cell unedited. The cell editor allows only the following data to be entered: o Ro and Ri may be positive integer values between 1 and 1000 Ohms. o Loss values for any attenuator style may be positive values between 0.1 and 50 dB in 0.1 dB increments. Minimum Loss Pad Data entry for Minimum Loss Pad designs is similar, except that you enter only the values of Ro and Ri. Note that the Minimum Loss Pad in RESNET is designed with the larger impedance as Ri and the smaller as Ro. In an actual circuit, you may physically reverse the pad elements so that R2 is at the input of the pad and R1 is at the output. Note that R2 remains the resistor to ground and R1 the resistor in series in this reversed configuration. Resistor Divider For Resistor Divider designs, you enter attenuation in dB, and Rs, the equivalent source resistance of the network, in kOhms, and RESNET does the rest. Remember that the values calculated by RESNET for a Resistor Divider assume a voltage source drive with zero source resistance and a load resistance much greater than Rs. Generally, if the source resistance is less than one tenth of Rs and the load resistance is greater than 10 times Rs, the resulting attenuation will be no more than 10% higher than the desired value. Voltage Divider For Voltage Dividers, you enter the maximum positive voltage, V+, the minimum negative voltage, V-, the output voltage, Vo, and the bias current, I. Note that the units are Volts and milliamperes (V, mA) for supply voltages and bias currents. Positive or negative voltages may be used, but V+ must always be greater than V-, and I is assumed to be a positive current. Naturally, the value of Vo must lie between the values of V+ and V-. WE'RE HERE TO HELP If you have problems using RESNET or have suggestions that you believe would improve the program, please contact us at Notor Research.