uBitX v.6 schematic / driver and finals transistor symbols / #ubitxv6 #v6
|
Folks,
On Farhan's schematic for v.6, the pre-drivers, drivers, and finals transistors are drawn in a way I've never seen before. There's solid lines from the base of one transistor through the circle body of the transistor to the base of the next transistor. Examples include Q911 & Q912, Q92 & Q93, etc. Is this a shorthand way of drawing parallel transistors (i.e., the bases are connected together)? Thanks! Todd K7TFC |
|
I've seen that on other schematics. Where there are more than one with the same arrangement of accompanying resisters, etc., the line is dashed and the notation "Q1, ... Qn" is written above the line to designate the transistors in the string.. It's done to conserve space on the paper and to avoid unnecessary confusion. Want to talk about confusion with schematics? I worked for a machine tool company in New York for a year and one engineer owned his own machine tool company in the Philippines previously and he designed an automatic system for cutting rods into threaded shafts with all kinds of beveled areas, reliefs and retaining slots. The drawing for the machine was 40-ft long... The machine cut a shaft automatically in less than half an hour that took four times that when done by a human and with much more precision. Such machines are fascinating to watch, much like the first time you see a plotter drawing up a written document with fancy fonts, etc. I know a draftsman/designer (WB4RVN) who can draw script that looks like it was done by a machine. I'm sure there are others equally talented. These people are artists in their own right. Calligraphy is indeed an art. Bob 鈥� KK5R
On Saturday, November 21, 2020, 9:31:00 PM EST, Gordon Gibby <docvacuumtubes@...> wrote:
Yes, they are in parallel. I was confused the first time I saw that with an earlier schematic years ago and checked it out. 听(look at the actual board)鈥� On Nov 21, 2020, at 20:21, Mick <Mgsebele@...> wrote:
|
|
hello,
I had already asked the question, but I did not get an answer on the schematic听 of ubitx 6, there are like 2 transistors mounted in parrallele on the final stage We see an IRF510 and a RD15HV in //. Maybe it鈥檚 a choice of transistor?听You put one or the other? I don鈥檛 quite understand the diagram for traduction fron Italien, try reverso Avevo gi脿 posto la domanda, ma non ho avuto risposta sul piano dell'ubitx 6, ci sono come 2 transistor montati in parrallele sul piano finale Vediamo un IRF510 e un RD15HV in parallelo. Potrebbe essere una scelta di transistor?听Si mette uno o l'altro? Non capisco lo schema Loris, se capisci questo, 猫 che Reverso non funziona troppo male cdt |
|
Yes, you can use one or the other but not both. The pinout is different so Farhan has provided for both
toggle quoted message
Show quoted text
solder pads. Raj At 22/11/2020, you wrote:
hello, |
|
It is common for a draftsman to use the double-slash ("//") tp denote a line that continues. Some use the double-tilde ("~~") instead. It is done to denote a "broken line" where it only means that a much too long line lengthens over a section of the drawing. I is an 'unspecified length' ... nothing more. I can, however, see it as an indication that one's particular radio may be opened and one or the other transistor may be found installed as the final transistor since the two may be electrically identical but made by different manufacturing firms and the particular firm's identification marking may be found on that transistor. It could be that the manufacturer of the transistors is the same, the marking only is printed on the transistor as bought/contracted by the buyer. At one time there were over 250 brands of tires offered in America and only 17 manufacturers. When I worked many years ago in a radio-TV shop, there was a l17-inch BW TV that when opened was found to be identical but sold under four different brands; even the diagrams used the part numbers of the different brands but the schematic was identical. Japan at one time had a catalog of cassette tape drives which were offered to different sellers so they could be put in their cases and sold as THEIR cassette players, many buyers not suspecting that the cassette they purchased was identical to the one sold for XX dollars less/more but they chose the machine they bought because the box it was in appealed more to their likes and taste. We live in a sometimes confused world. Bob 鈥� KK5R
On Sunday, November 22, 2020, 6:07:19 AM EST, Gerard <kabupos@...> wrote:
hello, I had already asked the question, but I did not get an answer on the schematic听 of ubitx 6, there are like 2 transistors mounted in parrallele on the final stage We see an IRF510 and a RD15HV in //. Maybe it鈥檚 a choice of transistor?听You put one or the other? I don鈥檛 quite understand the diagram for traduction fron Italien, try reverso Avevo gi脿 posto la domanda, ma non ho avuto risposta sul piano dell'ubitx 6, ci sono come 2 transistor montati in parrallele sul piano finale Vediamo un IRF510 e un RD15HV in parallelo. Potrebbe essere una scelta di transistor?听Si mette uno o l'altro? Non capisco lo schema Loris, se capisci questo, 猫 che Reverso non funziona troppo male cdt |
|
I just KNEW there was a logical and simple answer to this. Same item electrically but in a different "box." Bob 鈥� KK5R
On Sunday, November 22, 2020, 6:13:09 AM EST, Raj vu2zap <rajendrakumargg@...> wrote:
Yes, you can use one or the other but not both. The pinout is different so Farhan has provided for both solder pads. Raj At 22/11/2020, you wrote: >hello, >I had already asked the question, but I did not get an answer >on the schematic听 of ubitx 6, there are like 2 transistors mounted in parrallele on the final stage >We see an IRF510 and a RD15HV in //. >Maybe it鈥檚 a choice of transistor? You put one or the other? >I don鈥檛 quite understand the diagram |
|
Bob,
Yes!!! When my mother bought her first colour television in the '70s, I was watching through the grids.听The circuit boards were the same, only the selection buttons were different.听There was a price difference...for the same TV with a different brand!!!! The salesmen didn鈥檛 like it when you knew them. Even less now when you say you have checked on the net now (Especially auto mechanics car) LOL cdt |
开云体育This is a fair assessment. There are more limitations in the pre-driver stages at higher frequencies that would limit any gains made with the RD devices. 听Its better to start at Q90 and work towards the final amplifiers.听MRM 听 On Nov 22, 2020, at 8:54 AM, Evan Hand <elhandjr@...> wrote:
-- 鈥. _._ |
Mick
Bob Lunsford
Gerard
Raj vu2zap
MadRadioModder