Date   
Atachments

Sam Caldwell <samc@...>
 

G'day Troops,

I note that one or two contributors have mentioned attachments (which
do not appear).
At the same time there are some photographs which CAN be accessed.

Being a Bear of Very Little Brain, I would appreciate it if some kind
person would explain - particularly as in the near future there will
no doubt be proud builders anxious to display their new-born
transceivers.

Regards, Sam C.

Re: Atachments

Ashhar Farhan <farhan@...>
 

yahoo groups doesnt not retain attachments. if you can forward the
pictures to me, i canupload them on the folder.

i am new ot yahoo groups. i don't know if you can directly upload the
pictures without being a moderator.


- farhan

On Sat, 26 Jun 2004, Sam Caldwell wrote:

G'day Troops,

I note that one or two contributors have mentioned attachments (which
do not appear).
At the same time there are some photographs which CAN be accessed.

Being a Bear of Very Little Brain, I would appreciate it if some kind
person would explain - particularly as in the near future there will
no doubt be proud builders anxious to display their new-born
transceivers.

Regards, Sam C.





Yahoo! Groups Links




BITX20 component list

ik1zyw <pcravero@...>
 

Hi!
Has anyone attempted to list all BITX20 components? I haven't found
any link on Ashan's page. Here is my attempt at listing all
components, except for the IRF510 PA (had no time).

Please warn me off the list if corrections are needed.

73,
Paolo IK1ZYW


CAPACITORS
0.001u 2
0.1u 34
100p 3
10p 4
1u elec 2
2.2p 2
220p 3
22p var 6
365p var 1
47p 3
50u elec 6
560p 2
56p 1

RESISTORS 1/4W
10 9
22 1
100 13
220 14
470 2
100 lin 1
10k 3
10k lin 2
120k 2
1k 13
220k 1
2k2 1
2k2 9
4k7 3


XTAL
10MHz 5 (10)


TRANSISTOR
BC547 14
or 2N2222

IC
LM386-N1 1


DIODES
36V zener 1
9.1V zener 1
1N4148 13

TRANSFORMERS
INDUCTORS
see text

OTHER
Microphone 1
Loudspeaker 8ohm 1

Re: Atachments

Hans Summers <Hans.Summers@...>
 

i am new ot yahoo groups. i don't know if you can
directly upload the pictures without being a
moderator.
It's definitely possible, I am a member of another group where the members
do post pictures to the photos folder, and don't have to be administrator.
Have a look at the folders on the group home page
http://groups.yahoo.com/group/BITX20

I think the way it works is: if you send an attachment to the group, email
recipients do receive it. But people who have set up their account to not
receive emails, but instead use the web interface, cannot view the photos.
Therefore it's best to use the group folders rather than attach things.

73 Hans G0UPL
http://www.hanssummers.com

manhattan style pads

nd8i <bruceraymond@...>
 

I've been using ugly-style construction,
which has worked quite well. I've noticed
a bunch of constructors have used Manhattan-
style construction. Not being willing to
leave well enough alone, I want to give it
a try.

Where do people get the pads? Or how does
one make them from blank pcb material? I
suspect that trying to punch them out of
pcb material is a pretty slow and tedious
process, so I suspect there must be a better
alternative.

tia,
Bruce

Re: manhattan style pads

Mark Jones <Mark@...>
 

Bruce
 
I bought a "Copper island Construction Kit" but they ceased trading a while ago, I found someone (and I can't remember who or find the e-mails) that sent me some replacement (re-stock) pads via the GQRP reflector. I just paid the postage - a great deal and very helpful, he said that a friend of his was able to make them at work.
 
Sorry I can't help more - I thought about making some but it was just to tricky.
 
Mark. G0MGX

-----Original Message-----
From: nd8i [mailto:bruceraymond@...]
Sent: 26 June 2004 16:28
To: BITX20@...
Subject: [BITX20] manhattan style pads

I've been using ugly-style construction,
which has worked quite well.  I've noticed
a bunch of constructors have used Manhattan-
style construction.  Not being willing to
leave well enough alone, I want to give it
a try.

Where do people get the pads?  Or how does
one make them from blank pcb material?  I
suspect that trying to punch them out of
pcb material is a pretty slow and tedious
process, so I suspect there must be a better
alternative.

tia,
Bruce



Re: manhattan style pads

Hans Summers <Hans.Summers@...>
 

Mark, Bruce et al

I don't think the difference between "ugly" and "Manhatten" methods is all
that much.

My method is a bit of a hybrid I suppose. Mostly ugly. But if I find a point
needs to be better anchored I sometimes use a 10M resistor to ground (ok for
low impedance signal points) or a .22uF capacitor to ground (ok for dc
voltage points).

Sometimes I find I want pads. I mounted all the BITX20 inductors and
trifilar transformers on pads. But not nice circular pads like in the copper
island construction kit. I just find scraps of PCB stock and cut them up
into rough squares approximately 5mm x 5mm with a wire cutter. They're ugly
but it works and takes literally seconds.

73 Hans G0UPL
http://www.hanssummers.com

-----Original Message-----
From: Mark Jones <Mark@...>
To: BITX20@... <BITX20@...>
Sent: Sat Jun 26 16:39:19 2004
Subject: RE: [BITX20] manhattan style pads

Bruce

I bought a "Copper island Construction Kit" but they ceased trading a while
ago, I found someone (and I can't remember who or find the e-mails) that
sent me some replacement (re-stock) pads via the GQRP reflector. I just paid
the postage - a great deal and very helpful, he said that a friend of his
was able to make them at work.

Sorry I can't help more - I thought about making some but it was just to
tricky.

Mark. G0MGX

-----Original Message-----
From: nd8i [mailto:bruceraymond@...]
Sent: 26 June 2004 16:28
To: BITX20@...
Subject: [BITX20] manhattan style pads


I've been using ugly-style construction,
which has worked quite well. I've noticed
a bunch of constructors have used Manhattan-
style construction. Not being willing to
leave well enough alone, I want to give it
a try.

Where do people get the pads? Or how does
one make them from blank pcb material? I
suspect that trying to punch them out of
pcb material is a pretty slow and tedious
process, so I suspect there must be a better
alternative.

tia,
Bruce





Yahoo! Groups Sponsor
ADVERTISEMENT
click here



_____

Yahoo! Groups Links


* To visit your group on the web, go to:
http://groups.yahoo.com/group/BITX20/

* To unsubscribe from this group, send an email to:
BITX20-unsubscribe@...

* Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.

Components

g4dfv2004 <duncan.walters@...>
 

Many thanks Hans - my set of components arrived today!
Payment was sent straight away by first class post.
Keep up the excellent work!

Duncan G4DFV

Re: manhattan style pads

Bruce Raymond <bruceraymond@...>
 

Mark & Hans,
 
Many thanks for your replies.  Small rectangular pads should work just
fine, and those I can come up with - I don't know why it didn't occur to
me.
 
Thanks for your help,
Bruce/nd8i
 

-----Original Message-----
From: Hans Summers [mailto:Hans.Summers@...]
Sent: Saturday, June 26, 2004 1:47 PM
To: 'BITX20@...'
Subject: Re: [BITX20] manhattan style pads


Mark, Bruce et al

I don't think the difference between "ugly" and "Manhatten" methods is all
that much.

My method is a bit of a hybrid I suppose. Mostly ugly. But if I find a point
needs to be better anchored I sometimes use a 10M resistor to ground (ok for
low impedance signal points) or a .22uF capacitor to ground (ok for dc
voltage points).

Sometimes I find I want pads. I mounted all the BITX20 inductors and
trifilar transformers on pads. But not nice circular pads like in the copper
island construction kit. I just find scraps of PCB stock and cut them up
into rough squares approximately 5mm x 5mm with a wire cutter. They're ugly
but it works and takes literally seconds.

73 Hans G0UPL
http://www.hanssummers.com

Re: manhattan style pads

Wes Hayward <w7zoi@...>
 

Hi All,
 
Actually, I think that the Manhattan in the QRP construction method really refers to the use of straight wires on a 90 degree grid.   At least that is where the term originated.     Typical integrated circuits use a layout that follows a Manhattan format.  A recent reference is John Baliga, "Chips Go Vertical," IEEE Spectrum, March, 2004, pp43-47.    
 
I agree with Hans -- I have really seen no difference between construction on a ground plane when using pads and building without them, other than building without is faster.      There is rarely a need to go as high as 10M with the resistors if you don't have them around.   Something much smaller values will work just as well.
 
My son and I picked the term "ugly" on our 1981 QST paper "The Ugly Weekender" for a specific reason:   We wanted to emphasize that there is no relationship between circuit performance and the "pretty" nature of the construction, including that on a printed board.   In this case, it is the use of extensive ground plane that makes the circuitry work well.
 
73, Wes
W7ZOI
 

----- Original Message -----
Sent: Saturday, June 26, 2004 10:47 AM
Subject: Re: [BITX20] manhattan style pads


Mark, Bruce et al

I don't think the difference between "ugly" and "Manhatten" methods is all
that much.

My method is a bit of a hybrid I suppose. Mostly ugly. But if I find a point
needs to be better anchored I sometimes use a 10M resistor to ground (ok for
low impedance signal points) or a .22uF capacitor to ground (ok for dc
voltage points).

Sometimes I find I want pads. I mounted all the BITX20 inductors and
trifilar transformers on pads. But not nice circular pads like in the copper
island construction kit. I just find scraps of PCB stock and cut them up
into rough squares approximately 5mm x 5mm with a wire cutter. They're ugly
but it works and takes literally seconds.

73 Hans G0UPL
http://www.hanssummers.com


-----Original Message-----
From: Mark Jones
To: BITX20@...
Sent: Sat Jun 26 16:39:19 2004
Subject: RE: [BITX20] manhattan style pads

Bruce

I bought a "Copper island Construction Kit" but they ceased trading a while
ago, I found someone (and I can't remember who or find the e-mails) that
sent me some replacement (re-stock) pads via the GQRP reflector. I just paid
the postage - a great deal and very helpful, he said that a friend of his
was able to make them at work.

Sorry I can't help more - I thought about making some but it was just to
tricky.

Mark. G0MGX

-----Original Message-----
From: nd8i [mailto:bruceraymond@...]
Sent: 26 June 2004 16:28
To: BITX20@...
Subject: [BITX20] manhattan style pads


I've been using ugly-style construction,
which has worked quite well.  I've noticed
a bunch of constructors have used Manhattan-
style construction.  Not being willing to
leave well enough alone, I want to give it
a try.

Where do people get the pads?  Or how does
one make them from blank pcb material?  I
suspect that trying to punch them out of
pcb material is a pretty slow and tedious
process, so I suspect there must be a better
alternative.

tia,
Bruce





Yahoo! Groups Sponsor     
ADVERTISEMENT
click here     
     


  _____ 

Yahoo! Groups Links


*      To visit your group on the web, go to:
http://groups.yahoo.com/group/BITX20/
 
*      To unsubscribe from this group, send an email to:
BITX20-unsubscribe@...
 
*      Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.



Please suggest for alternative 'linear amplifier module'

MILAREPA <MILAREPA@...>
 

Dear forum,
The IRF510 and 2N2218 is not available here in INDONESIA,
 
-Could you suggest an alternative for 'linear amplifier module' ?
 
-Can I just use:
HF BANDS QRP LINEAR AMPLIFIER - 4WATT or
TEN WATT LINEAR AMPLIFIER all by Harry Lythall - SM0VPO
Since 2SC.....( Japanese) transistors are available here.
 
 
-What  module ( coil, capacitor, x-tals) to change if need another band say 10MHz ?
 
Thank you.

Audio amp schematic

Mark <Mark@...>
 

Anyone checked this - is +V on pin 5 correct?

Should it not be on pin 6?

Mark.

PCB

Bill Schofield <g0bak-m@...>
 

Hi all. I have posted a pic, I hope in the photos section. This is my
first attempt at using Press & Peel to create PCB's as I usually use
the island method etc for my projects. I was so impressed with the
results, to say this was my first attempt, I made the effort to tell
you all about it. See the site at
http://www.ronlin.co.uk/pressnpeel.html
I wish everyone good luck with the project. While I think on, Plumb
Centre in the UK have a 1/2" Delta Tap Washer Cat No C54018 in stock.
The price is £1.80 plus VAT for 10 washers. Not sure if they will
post but they have branches everywhere. All the best, de Bill G0BAK.

Re: Audio amp schematic

Charles Darley
 

Hi
 
according to my diagram  +V should be on pin 6 as mentioned ..
 
looks like pins 5 and 6 need to be changed for each other as output must be on 5 and volts in on 6
 
Charles G4VSZ

-----Original Message-----
From: Mark [mailto:Mark@...]
Sent: 27 June 2004 09:47
To: BITX20@...
Subject: [BITX20] Audio amp schematic

Anyone checked this - is +V on pin 5 correct?

Should it not be on pin 6?

Mark.


Re: Audio amp schematic

Ashhar Farhan <farhan@...>
 

mark,
check the corrected schematic on http://www.phonestack.com/farhan.
the earlier circuit had a typo.
- farhan

On Sun, 27 Jun 2004, Mark wrote:

Anyone checked this - is +V on pin 5 correct?

Should it not be on pin 6?

Mark.





Yahoo! Groups Links




filter shielding?

Chris van den Berg
 

Hi all,
I had the intention to build this transceiver when a friend of me
brought this Yahoo group under my attention.
Too bad, now I spend all the time on reading all information instead
of building it ;-)
The nice thing I like is that the design is so basic, so
straightforward and everything (except the final stage) broadband
that it can be adjusted easily to everyones needs.

Because I have several x-tals with a frequency of 4.9152 MHz this
will be the IF frequency and because I want to make it for 18 Mhz, I
will try to cover the phone part with a VXO on about 13 MHz.

Looking at the pictures of other builders, I see several 'islands',
I do not build that way, I just solder every component to each other
(above the copper surface, only connected to it where needed).

What I also saw is that the x-tal filter has no kind of shielding.
Is it worth seperate the input/output of the filter with a kind of
shielding to prevent the signal passing it?

Good luck all,
Chris, PA3CRX

Re: PCB

Hans Summers <Hans.Summers@...>
 

While I think on, Plumb Centre in the UK have a 1/2"
Delta Tap Washer Cat No C54018 in stock. The price
is £1.80 plus VAT for 10 washers. Not sure if they
will post but they have branches everywhere. All
the best, de Bill G0BAK.
What is a "delta" tap washer? I'd be careful... When I bought my tap washers
there were "delta" washers and ordinary ones. But I don't recall what the
difference was. Anyone know?

I got my (non-"delta") washers at my local hardware store where they sell a
pacl of 3 for £0.45 including VAT. I'm happy to send some to whoever wants
them. Farhan is also talking of sending me 1000 from India, and the TV
baluns.

73 Hans G0UPL

(Again owing many people emails, pls QRX)

Re: filter shielding?

Jim Strohm <jstrohm@...>
 

On Jun 27, 2004, at 6:16 AM, vdberghak wrote:

Looking at the pictures of other builders, I see several 'islands',
I do not build that way, I just solder every component to each other
(above the copper surface, only connected to it where needed).
The only reason(s) I can think of _not_ to make 'em float in the air is that this technique has the potential to make the circuit sensitive to microphonics. And in a high-vibration or high-shock environment such as portable or mobile use, the solder joints would tend to fracture and eventually cause intermittent failures long before any visual breakage was apparent.

What I also saw is that the x-tal filter has no kind of shielding.
Is it worth seperate the input/output of the filter with a kind of
shielding to prevent the signal passing it?
Well, you could take the PCB scraps you saved by not using "island" construction, and use it to make shielding.

What's that old bromide -- "You can never be too rich, too thin, or have too many friends" -- add to that the idea that your electronics can never have too much shielding.

Jim N6OTQ

Re: Please suggest for alternative 'linear amplifier module'

Jim Strohm <jstrohm@...>
 

On Jun 26, 2004, at 11:03 PM, MILAREPA wrote:

Dear forum,
The IRF510 and 2N2218 is not available here in INDONESIA,
 
-Could you suggest an alternative for 'linear amplifier module' ?
 
-Can I just use:
HF BANDS QRP LINEAR AMPLIFIER - 4WATT or
TEN WATT LINEAR AMPLIFIER all by Harry Lythall - SM0VPO
Since 2SC.....( Japanese) transistors are available here.
Both those circuits will work fine, as will most any other QRP amp
circuit. A broadbanded circuit is easier to build and use because it
requires no tune-up and is less likely to have a parasitic oscillation.
Be aware that those two amps NEED a low-pass output filter. For 20M,
the BITX20 filter will be fine. For other frequencies, most popular
radio handbooks have equations and design examples for the frequency of
interest.

Readers are reminded that Harry SM0VPO likes to share his work, but
doesn't like seeing others pirate it or claim it as their own. So be
sure to provide attribution (as was done here) when you share his
stuff. He has the best homebrew radio site in the world, and we'd like
to encourage him to keep it online, by respecting his work and his
copyright.

Jim N6OTQ

IF amp pcb

vk3bfa <ablight@...>
 

Hello Fello wBuilders,
think I stuffed up a previous message post - anyway, have posted a
photo of my humble efforts at kitchen sink PCB making for the BITX20
IF Amp - its in the VK3BFA folder. Any comments on probable mistakes
welcome - will try and load it with components tomorrow if I can
ignore customer jobs already on the work bench hi hi. I build on the
track side of the PCB (semi ugly/manhattan) - so much easier to
troubleshoot.....
73 de VK3BFA Andrew