From: Thomas F. B. <tho...@gm...> - 2006-05-12 13:38:36
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Dear QUCS-team! First of all: Great Job you did, and you are still doing! I have two suggestions to improve the program: 1. Suggestion: When drawing the circuit of MicroStripLine it is not clear which end is which port. For instance, for the Tee the widths w1, w2 and w3 appear in the drawing but not the port designation itself. I guess the port with the two tiny dashes is port 1, but the others? I attached a png-file "MSL_portnumbering.png" to illustrate what I mean. There I wrote to each port the port number (which may not be true!). It would be nice to print the port numbers into the schematic. 2. Suggestion: The reference planes of e.g. a MSL-Tee or a MSL-Cross are not given, at least I did not see it. It is quite cumbersome to check the related literature (mainly old publications) to find something about the reference planes. Since there are several possibilities to define the reference planes of e.g. a MSL-Tee or a MSL-Cross it would be good to give those reference planes in the documentation. Again, to illustrate my problem, I attached two files named "MSL_reference.png" and "MSL_coupler.png" which show two of several possibilities. In the figure "MSL_coupler.png" it is (hopefully) obvious that the physical layout and therefore the electrical performance of the MSL circuit which will be produced, depends on the reference planes. (By the way, the reference planes shown in case A are those used in the program Linmic.) So far so good, and thanx for your time and efforts Thomas Bechteler ========================================= Dr. Thomas F. Bechteler Izmir Institute of Technology Faculty of Engineering Department of Electrical and Electronics Engineering TR-35430 Gulbahcekoyu, Urla/Izmir Turkey Tel.: +90 / 232 / 750-6348 FAX : +90 / 232 / 750-6196 e-mail: tho...@iy... ========================================= -- "Feel free" - 10 GB Mailbox, 100 FreeSMS/Monat ... Jetzt GMX TopMail testen: http://www.gmx.net/de/go/topmail |
From: Stefan J. <st...@gr...> - 2006-05-18 05:51:15
Attachments:
tline_1.png
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Am Do, 18.05.2006, 07:35, schrieb Thomas F. Bechteler: > Hello Stefan, Hi! >> > Holy smokes, that is good news ... For one of my courses >> > I already proposed QUCS to my students. With the new >> > release we would be able to simulate >> > a transmission line (ideal) in the transient analysis. >> >> Have you already tried that feature? > > I tried the circuit which is attached to this e-mail. > V0 and Vout show the pulse(s). You mean V0 and Vin? > But Vout is always zero. > With the very same circuit the program Pspice "shows" the output pulse(s), > and when the load resistor R2 is changed also the reflections > can be observed. > Maybe I do something wrong ... I just tried the circuit (see attachment). It looks like it's working. Keep in mind that this has been done using latest CVS. It does not work with 0.0.8... Stefan. |
From: Stefan J. <st...@gr...> - 2006-05-18 06:18:10
Attachments:
tline_2.png
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Am Do, 18.05.2006, 08:04, schrieb Thomas F. Bechteler: > Hi! Hello again, >> > But Vout is always zero. >> > With the very same circuit the program Pspice "shows" the output >> > pulse(s), and when the load resistor R2 is changed also the >> reflections >> > can be observed. >> > Maybe I do something wrong ... >> >> I just tried the circuit (see attachment). It looks like it's working. >> Keep in mind that this has been done using latest CVS. It does not >> work with 0.0.8... > > I do use 0.0.8, since I prefer the latest stable ("official") releases. > Nevertheless, it seems from your plot-file that the > delay time of the transmission line is not included in the > model. In Pspice there is a clearly observable delay time > between Vin and Vout in the nanosecond range. Ah. Sorry. My mistake. Please see attachment. L=0.3m means 0.3mm, but 0.3 is now really 0.3 meters. Cheers, Stefan. |