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Re: [2] Nicely drafted BITX schematics.
Arv Evans
Then both of you did good work!
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On Sunday 14 August 2005 08:27 am, Ron McDowell - W5RCM / ZS1MCD wrote:
I don't get credit for that... eternalsquire did the work...I just |
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Re: [3] Nicely drafted BITX schematics.
Ron McDowell - W5RCM / ZS1MCD
Hey Eternal Squire,
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If you make any changes to your bmps, let me know and I'll remake the gifs. -- 72, Ron - W5RCM / ZS1MCD Austin TX / Hermanus ZA On 14 Aug 2005 18:26:54 +0100, [Rahul Srivastava <vu3wjm@...>] wrote:
--0-175253323-1124040414=:11736 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Hi! Ron! Thanks for all the efforts . The automated system appears to have some flaws. My observations 1) Zobel at output pin 5 of 386 has cap marked 100pf this appers to be an error, similarly spk cpuling cap value is 1uF , this again highly on low side. 2) Driver stage has the 1K resistor going to ground from base before the coupling cap this again slight at err. Just in case it does not confusion. Never the less very good work. 73 Raahul VU3WJM Ron McDowell - W5RCM / ZS1MCD <w5rcm@...> wrote: I don't get credit for that... eternalsquire did the work...I just converted his BMPs to GIFs. -- 72, Ron - W5RCM / ZS1MCD Austin TX / Hermanus ZA --------------------------------- Yahoo! Messenger NEW - crystal clear PC to PC calling worldwide with voicemail --0-175253323-1124040414=:11736 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit <html><body> <DIV>Hi! Ron!</DIV> <DIV> </DIV> <DIV>Thanks for all the efforts .</DIV> <DIV>The automated system appears to have some flaws. My observations</DIV> <DIV> </DIV> <DIV>1) Zobel at output pin 5 of 386 has cap marked 100pf this appers to be an error, similarly spk cpuling cap value is 1uF , this again highly on low side.</DIV> <DIV> </DIV> <DIV>2) Driver stage has the 1K resistor going to ground from base before the coupling cap this again slight at err. </DIV> <DIV> </DIV> <DIV>Just in case it does not confusion. Never the less very good work.</DIV> <DIV> </DIV> <DIV>73</DIV> <DIV> </DIV> <DIV>Raahul VU3WJM</DIV> <DIV> </DIV> <DIV> </DIV> <DIV> </DIV> <DIV> </DIV> <DIV><BR><BR><B><I>Ron McDowell - W5RCM / ZS1MCD <w5rcm@...></I></B> wrote:</DIV> <BLOCKQUOTE class=replbq style=PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid><TT>I don't get credit for that... eternalsquire did the work...I just converted his BMPs to GIFs.<BR>--<BR>72, Ron - W5RCM / ZS1MCD<BR>Austin TX / Hermanus ZA<BR><BR><BR></TT></BLOCKQUOTE><p> <hr size=1><font size=2 face=Verdana, Arial, Helvetica, sans-serif><a href= Yahoo! Messenger</a><font color=red>NEW</font> - crystal clear PC to PC <a href= calling worldwide with voicemail</a></font> <!-- |**|begin egp html banner|**| --> <br> <div style=text-align:center; color:#909090; width:500px;> <hr style=border-bottom:1px; width:500px; text-align:left;> <tt>YAHOO! GROUPS LINKS</tt> </div> <br> <ul> <tt><li type=square> Visit your group <a href=>BITX20</a> on the web.<br> </tt> <tt><li type=square> To unsubscribe from this group, send an email to:<br> <a href=mailto:BITX20-unsubscribe@...?subject=Unsubscribe>BITX20-unsubscribe@...</a><br> </tt> <tt><li type=square> Your use of Yahoo! Groups is subject to the <a href=>Yahoo! Terms of Service</a>.</tt> </ul> <br> <div style=text-align:center; color:#909090; width:500px;> <hr style=border-bottom:1px; width:500px; text-align:left;> </div> </br> <!-- |**|end egp html banner|**| --> </body></html> --0-175253323-1124040414=:11736-- ___________________________________ Free Web Space for your Amateur Radio Hobby! |
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Re: [2] Nicely drafted BITX schematics.
Rahul Srivastava
Hi!? Ron!
?
Thanks for all the efforts .
The automated system appears to have some flaws. My observations
?
1) Zobel at output pin 5 of 386 has?cap marked 100pf this appers to be an error, similarly spk cpuling cap value is 1uF , this again highly on low side.
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2) Driver stage has the 1K resistor going to ground from base before the coupling cap this again slight at err.
?
Just in case it does not confusion. Never the less very good? work.
?
73
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Raahul VU3WJM
?
?
?
?
Ron McDowell - W5RCM / ZS1MCD wrote: I don't get credit for that... eternalsquire did the work...I just converted his BMPs to GIFs.
NEW - crystal clear PC to PC |
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Re: [2] Nicely drafted BITX schematics.
Ron McDowell - W5RCM / ZS1MCD
I don't get credit for that... eternalsquire did the work...I just converted his BMPs to GIFs.
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-- 72, Ron - W5RCM / ZS1MCD Austin TX / Hermanus ZA On 14 Aug 2005 08:24:46 -0600, [Arv Evans <arvevans@...>] wrote:
Ron W5RCM Very good job on the schematics. This should also help a lot for those who want to do their BITX as modules. Thanks, Arv K7HKL On Sunday 14 August 2005 08:05 am, Ron McDowell - W5RCM / ZS1MCD wrote: Very nice job, Eternal Squire! Yahoo! Groups Links ___________________________________ Free Web Space for your Amateur Radio Hobby! |
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Re: Nicely drafted BITX schematics.
Arv Evans
Ron W5RCM
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Very good job on the schematics. This should also help a lot for those who want to do their BITX as modules. Thanks, Arv K7HKL On Sunday 14 August 2005 08:05 am, Ron McDowell - W5RCM / ZS1MCD wrote:
Very nice job, Eternal Squire! |
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Re: Nicely drafted BITX schematics.
Ron McDowell - W5RCM / ZS1MCD
Very nice job, Eternal Squire!
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I have converted these to GIF format... you can grab them all from -- 72, Ron - W5RCM / ZS1MCD Austin TX / Hermanus ZA On 14 Aug 2005 08:09:23 -0000, [eternalesquire <eternalsquire@...>] wrote:
All, I'm starting to need reading spectacles, so I took the liberty of redrafting the schematic submitted by Mr. Farhan into a series of modular documents that should take somewhat less effort to view finer details such as decimal points. I tried as hard as I could to make them reflect best engineering practices as I currently understand them. I've incorporated what appear to be the most popular modifications I've seen in this group to date that also keep to the spirit of requireing only those parts reasonably obtainable in India to an amateur of limited finances. I've also imade annotations derived from Mr. Farhan's text where appropriate for clarity. The source documents were drawn using the latest version of LTSpice, available from the Linear Technology website. I then exported them into Word bitmap files. Finally, I retouched those files to add details not available from LTSpice, such as variable capacitors. Please note that the LTSpice diagrams themselves are not runnable, I merely used the tool as a drafting aid. Please feel free to make corrections as appropriate. One thing I would recommend is other sets of capacitor values for different IF frequencies. I hope others will add to Table 1 in TRANSCEIVER.bmp, more working choices for IF's besides 9 and 10 Mhz. You'll find this archive uploaded into as EGR\BITX.zip Enjoy, The Eternal Squire ___________________________________ Free Web Space for your Amateur Radio Hobby! |
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Re: New to group and Query
ajparent1
Hello,
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I have it on paper and in the chassis. It's still pending getting it to an electronic form. Basic design isa fairly stock PI form and uses 4 diodes to attain about 40-45db of attenuation. Input and output impedences are 50 ohms. Allison --- In BITX20@..., "vdberghak" <vdberghak@z...> wrote:
Did I miss this attenuator? I am interrested to see the schematic (and |
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Re: Nicely drafted BITX schematics.
ajparent1
Hello,
Is it possible to make those Word bitmap files intosomething like HTML or other more portable format? Reason? I do not use Word and do not have it. Allison KB1GMX --- In BITX20@..., "eternalesquire" <eternalsquire@c...> wrote: All, |
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Re: New to group and Query
Did I miss this attenuator? I am interrested to see the schematic (and
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if someone build it, the results). Thanks, Chris. --- In BITX20@..., "ajparent1" <kb1gmx@a...> wrote:
In the RX |
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New file uploaded to BITX20
Hello,
This email message is a notification to let you know that a file has been uploaded to the Files area of the BITX20 group. File : /BITX 20 V1,2&3 /Ver3 PCB ddouble sided/dimenV3.pdf Uploaded by : vu3wjm <vu3wjm@...> Description : Dimensions for Ver3 PCB valid for both single and doublesided. You can access this file at the URL: To learn more about file sharing for your group, please visit: Regards, vu3wjm <vu3wjm@...> |
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Double sided layout for Ver3
vu3wjm
Hi!
Few friends have shown interest in making a double sided board for BITX with top layer unetched and acting earth plane. I have uploaded the artwork files to make it easy for them. Missing hole on a 100E resistor in collector line of Q12 has been also corrected. 73 Rahul VU3WJM |
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New file uploaded to BITX20
Hello,
This email message is a notification to let you know that a file has been uploaded to the Files area of the BITX20 group. File : /BITX 20 V1,2&3 /Ver3 PCB ddouble sided/xray V3DOUBLE.pdf Uploaded by : vu3wjm <vu3wjm@...> Description : X ray view You can access this file at the URL: To learn more about file sharing for your group, please visit: Regards, vu3wjm <vu3wjm@...> |
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Re: New to group and Query
Rahul Srivastava
Hi!
?
It would be a simple matter to upload the interconnection traces only less the?earth plane. I will simply reamove the earth plane from V3 layout.
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Friends wishing to use a double sided board can leave the top layer unetched and countersink the non grounded connections.
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Thankfuly being sunday will do that over next hour.
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73
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Rahul VU3WJM
ajparent1 wrote: .
To help you stay safe and secure online, we've developed the all new . |
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Nicely drafted BITX schematics.
eternalesquire
All,
I'm starting to need reading spectacles, so I took the liberty of redrafting the schematic submitted by Mr. Farhan into a series of modular documents that should take somewhat less effort to view finer details such as decimal points. I tried as hard as I could to make them reflect best engineering practices as I currently understand them. I've incorporated what appear to be the most popular modifications I've seen in this group to date that also keep to the spirit of requireing only those parts reasonably obtainable in India to an amateur of limited finances. I've also imade annotations derived from Mr. Farhan's text where appropriate for clarity. The source documents were drawn using the latest version of LTSpice, available from the Linear Technology website. I then exported them into Word bitmap files. Finally, I retouched those files to add details not available from LTSpice, such as variable capacitors. Please note that the LTSpice diagrams themselves are not runnable, I merely used the tool as a drafting aid. Please feel free to make corrections as appropriate. One thing I would recommend is other sets of capacitor values for different IF frequencies. I hope others will add to Table 1 in TRANSCEIVER.bmp, more working choices for IF's besides 9 and 10 Mhz. You'll find this archive uploaded into as EGR\BITX.zip Enjoy, The Eternal Squire |
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Re: New to group and Query
ajparent1
--- In BITX20@..., "bambazonke01" <jimandruth@s...> wrote:
Hi, Inline comments. ---It showed on my 20m on the bench as a hetrodyne with modulation. with shielding it was less pronounced but I'm near Boston. I will have to consider some other IF frequency. First I'll have toWell if you get some 9.6mhz crystals as they are common and usually cheap. Did you know that TEn Tec used to use CB crystals for their earlyYes, third overtone 27mhz. I've experimented with them and they worked but not to my likeing. fundamental frequency gave 9 mHz. That is why the filters wereYep, imaging transceivers were very popular. Crystals for 9mhz ladder filters are easy to get as that is also another microporcessor crystal. Another possible band image TRX is 30m and 17m using 4.0mhz IF and 14mhz VFO. I was searching through packing crates today for my PC manufacturingCool. Over the years I've used every technique from the most primitive to advanced CADD based with commercial expose, develope and etch systems. Nice for n>1 runs but dead bug[ugly or manhattan] is faster for one off. I put a block diagram of a PLL I use for many uses in the FILES section. I've reproduced it many times using different (but similar) Pll chips. Regards, Allison KB1GMX |
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New file uploaded to BITX20
Hello,
This email message is a notification to let you know that a file has been uploaded to the Files area of the BITX20 group. File : /KB1GMX/Plldesign.pdf Uploaded by : ajparent1 <kb1gmx@...> Description : block diagram of PLL for 6m BIT-X You can access this file at the URL: To learn more about file sharing for your group, please visit: Regards, ajparent1 <kb1gmx@...> |
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Re: New to group and Query
bambazonke01
---
Hi Allison, I'd never thought of WWV being a problem in this respect in North America. You are right.It would be annoying to hear that Tick -tick all the time. I will have to consider some other IF frequency. First I'll have to see what crystals are available locally and redesign the ladder filter. Did you know that TEn Tec used to use CB crystals for their early filters? The 27+ Mhz crystals are 3 rd ovetone types so operating on the fundamental frequency gave 9 mHz. That is why the filters were slightly above 9 mhz. I like the idea of 9 Mhz as with the 5 to 5.5 Mhz VFO we could operate 2 bands (80 and 20) I was searching through packing crates today for my PC manufacturing stuff without finding any. Some where I have a great setup of ultra violet light and timer etc. I may have to go out and buy new ones. 73 Jim VE3DDY |
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Re: New to group and Query
ajparent1
Hello,
Comments are inserted inline. --- In BITX20@..., "bambazonke01" <jimandruth@s...> wrote: Most of this V3 board is IF and BFO and as such is well shielded byI prefer a two sided board where the component side has no traces only clearance holes for non grounded components and holes that are not clearanced so grounded components can be soldered to it the ground plane. The bottom then only has +power and signals simplifying layout. The inherent shielding is excellent with this layout and only side need be "drawn". I have found shielding is always helpful. For those of us here(USA) or near WWV at 10mhz can be problematic. To get up to 6 meters I would presume you are going to heterodyneThis will be the 6th design for 6m I've done. Each being significantly different in some way from previous. This will be the first using a bidirectional IF and single conversion. Design #5 is a BIT-X at 20m driving a TenTec 1208(or any other!) transverter for 6M naking it dual conversion. That design (#5) will be modded for 10M use and a later 432mhz transverter. It's not nearly the problem if the frequencies are chosen right and the mixer is not overloaded. I have done many a hetrodyne LO before with excellent results. A VFO of 5mhz range and a crystal osc at 36mhz works with a 9mhz IF for coverage of 50.0 to 50.5mhz. The VFO and Crystal osc can be in the same module with a DBM and the DBM output goes to a seperate module with a three tuned circuit bandpass filter at 41mhz and output amplifer. Measured spurs were more than 70db down at the output of the filter amp module. Much of the work I've done with hetrodyne LO systems is well documented by others in EMDRF. However, this version will use a sampling PLL system of my design. I have four of these working in various radios with the only difference being the output frequency. The PLL is already complete and the whole module uses 70ma and provides a 10DBm output for the mixer in a package of 40mmx40mmx22mm. This verion will have a LO at 40.4 through 40.700 (tunes 50.0 to 50.300). I should gen up a block diagram of this system as it's somewhat simpler and does not require a microprocessor for tuning. Variations on the BITx design I will be using is a commercial DBM for the mixer (I have a bunch of SBL1/anzac108). I will put a MPF102 fet preamplifier before the bandpass filter as it's fairly lossy and at 6m you need a good signal to noise for weak signals. In the RX path after Q1 a PIN(poor mans PIN, 1n4007) diode attenuator for RX AGC. AGC voltage will be audio derived. The amplifiers on the VHF side of the DBM will be 2n5109 or 2n5176 types (Ft >1ghz). The IF because of WWV will be 9.6mhz. Power amplifier chain will use a 2N4124, 2n5109 and 2SC1971. There may be other changes as I experiment. Power amplifier chain will be split fairly similar to the base BIT-x where the 2N4124 buffer (Q14) in on the main board and the driver and final on a seperate board. I do this for two reasons. I have a good quanitity of 2.4" wide G10 copper clad board strips of 50-60cm long and I may later wish a different power amp design. Hope this give some detail on how I will go about it. FYI: My passtime is QRP 6M and 2M weak signal work. Regards, Allison KB1GMX Best of luck |
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Re: New to group and Query
bambazonke01
Most of this V3 board is IF and BFO and as such is well shielded by
the prolific ground plane on it's single side.I like this type of layout as it avoids a lot of ground loop problems. To get up to 6 meters I would presume you are going to heterodyne the signal and have the final on a separate CCA. The hetrodyne oscillator and final can be seperately well shielded from the IF and VFO otherwise you are going to have more trouble than a barrel full of monkeys with all the signals mixing . Best of luck Jim VE3DDY --- In BITX20@..., "ajparent1" <kb1gmx@a...> wrote: wrote: I'mThe Far circuits boards are away too big for my application so insidestrongly considering a run of the CCA design by VU3WJM (Rahul). pcbthe Chinese 884 VHF packset which you can buy off E-bay (Call itand resist etc. muchdonehere.Secondly postage from India is also rather expensive ie for amorethan the board.Board is correct in all respect except for one hole missing quiteresistor but that anchors to nearby component lead. Ver3 is instable too. I would be happy if some DX friends can help out anythismatter to all those who need PCB. I will be happy to provide friendneeded file. thedoesindeed results in improved audio. I use 82,120&150pf caps asstandardvalue.section board884packset like a glove. I have to find someone who has that PCB'savailable or else gear up to make my own. I've made some forinthe past. I think Far Circuits may make me one as well. FMabout$120 Canadian or $100 US. These sets are good for 6 meter enjoy abutthey are ideal to use for a rebuild in an HF packset. theproject like this BitX. wrote:meantime, I'll start collecting components. ofincludingJim VE3DDY onvertical sectionsof blank PCB might allow parts of the circuit to be built iftheseshieldingpartitions, thus allowing a more compact design. veryyoudocumented inprefer thatmethod of construction. Some of the PCB layouts aresmallerthe FILESand PHOTO sections of the forum. tocompactlayout. intotheseveralFILES and thePHOTO sections and review what is there. You will findadditionalideas for modification and upgrades. whichproblems, thereare many now on the BITX forum that may be able to help. Terms ofI'dmodules.likeconfigurationto install a Bit-X perhaps for 40 Meters. HamService. ofradiosales allService. newYahoo! Security Centre. |
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Re: New to group and Query
ajparent1
Hi,
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It's size and the lack of two sides (top ground plane) make it less than useful for my 6m project. I'm saving it for something else. I mentioned it so others may know that FAR has it. Myself I'm dead bugging it [aka ugly or manhattan] style as its fast and offers good grounding and shielding. I have PCB making materials but for one off stuff it's as much time to setup and do that is just building it dead bug style. Also much smaller. FYI: I'm targeting a 175x45x130mm package. Power output will be in the 3-5w range with 2SC1971 transistor. So I understand you goal for containing in a manpack. Allison KB1GMX --- In BITX20@..., "bambazonke01" <jimandruth@s...> wrote:
The Far circuits boards are away too big for my application so I'm |
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