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More components
Hans Summers
The two extra sets are already accounted for! Seems I should have bought
more spares, but I didn't really want to be stuck with components and be unable to do anything with them. I can get more sets, but without the savings from getting 10+, 25+ and 100+ prices on some items, the price would be ?11.64 + postage (compared to ?8.19 for this bulk-purchased set). Alternatively, tell me you're interested and we'll wait say until next Wednesday same time (13:00 UK time) and see how many orders arrive. Perhaps get some quantity discounts again, if there are enough more people interested. What do people think? And if anyone needs any particular component and can't source it locally (e.g. IRF510 being sent to Baino in Singapore) then I can sort that out for you too, just email me. 72/3 de Hans G0UPL |
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2N3866
Jim
I did a little bit of poking around, and found that Mouser offers these at USD$1.50 each, or
$1.24 in 100-pc quantities. For stateside users, it might be possible to set up a volume buy and then distribute them -- US mail is $0.60. A 2 oz. Airmail Letter is $1.55 to India, $1.60 to many places in Western Europe. Mouser has no minimum order, but they ship UPS or Fedex, and it'll probably be around $5.00 for the smallest size pkg. I found some on ebay, but the seller's asking nearly twice the Mouser 100-pc price and he also charges rapacious shipping. For what it's worth ... Jim N6OTQ |
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Components
Hans Summers
开云体育?
I have now placed the bulk order for BITX20
components. I have emailed all those who asked for the components. If you
haven't heard from me then I have probably forgotten you in which case shout.
?
Due to a further bulk price reduction on the
crystals, and that the price quoted on the telephone ended up less than in the
catalogue, they were just ?0.223 each. The 2N2219A were also cheaper because
more than 10 were ordered. So the overall price came down a little.
?
I have ordered two extra complete sets in
case any newcomers want them, as listed below. The price is now ?8.19 for one of
these sets + postage at cost (?0.28 UK). I hope someone will want these sets
because otherwise I'll have them hanging around here doing nothing.
?
I also ordered some extra 10MHz crystals and
can provide them at ?2.23 per set of ten, + postage at cost.
?
One component set contains:
?
Qty 10 of 10.000 MHz crystals, HC49 style
Qty 25 of BC547B transistors
2N2219A driver transistor
IRF510 MOSFET
Qty 15 of 1N4148 diodes
36V Zener diode
9.1V Zener diode
5.6V Zener diode
LM386N-1 Audio Amp IC (correct variety)
Qty 5 of 2-22pF trimmer capacitor
Miniature tuning capacitor*
?
* NOTE: The tuning capacitor is one of the miniature kind as used in
portable radios. Size is 20.2 x 20.2 x 10.8mm. Control shaft is 6.6mm diameter
tapped with 2.6mm thread. Panel mounting is via twwo 2.6mm tapped screws next to
the control shaft. Capacitance: AM section 3.0 - 141.6pF, Oscillator section 4.0
- 59.2pF. So in parallel you'd have 200pF which is less than Farhan's design for
350pF. It might therefore be necessary to alter the VFO coil to get the required
tuning range.
?
72/3 Hans G0UPL
?
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?
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A really Exciting Project
John Fisher
开云体育Dear
Friends,
?
I have just read all of the
original posts to this new yahoo group, and I am delighted. This is a fun and
exciting project and I am recommending it to all my friends?in the Austin
QRP group. We have many builders here who might be delighted
to?make?this cool project. Thanks to all for bringing this together,
and especially to Ashhar Farhan for all of his work. It is truly a marvelous
project :-)
?
?
?Regards, ?John ?
Austin,
Texas
?
=============================================
email:????? k5jhf@... photos:??? files:??????? webpage:? callsign:??? K5JHF ============================================= ? |
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Re: Components from Rapid Electronics
Mr. D.Walters
开云体育Hans,
Please will you go ahead and include me in your
order?
I want the complete set of components?as shown
in your list?below.
Please email me your postal address details and I
will get
the total payment to you.
Best wishes
?
Duncan G4DFV
? |
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Re: What are tap washers ?
padmanabhan cattamanchi
Generally tap washers are used to fix leaky
taps/faucets. They are made of teflon or nylon and vary from 1/2 inch dia to 3/4 inch dia, with a hole in the centre which varies frfom 3mm to 4mm in dia. The thickness varies from 2mm to 3.5mm in dia. The size of the tap washers may vary from country to country. The best source for getting the tap washer would be the local hardware store or your plumber. Consult your plumber, he would direct you to the right place to get the tap washers. The BITX20 is a also a plumber's delight HI! 73,s paddy vu2pep __________________________________ Do you Yahoo!? Yahoo! Mail - 50x more storage than other providers! |
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Re: Components from Rapid Electronics
William Ford
开云体育Hans, I witheld my original cheque pending your
Email of today. I should like the full list as per your Email of 10.51 today and
will pay by Paypal as you suggest in uk pounds
Many thanks? jack ford G0tgp.
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Re: linear coil
Hans Summers
Hi ashhar, sorry to bother you but, I was wanting to know if 3uH i calculated 3uH on each winding.Don't forget Mark, it's a bifilar transformer with two windings, not just a single winding with a centre tap. 73 Hans G0UPL |
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Re: Fw: First QSO with the BITX20 Transceiver (fwd)
Hans Summers
The VFO and stabilizer are as large as the mainboard.Pete, what VFO stabilizer are you using? Is it Huff Puff? I love Huff Puff, and definitely intend to build a simple stabiliser for the BITX20 when I have the rest of it working. See my Huff Puff page for details: 73 Hans G0UPL |
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Components from Rapid Electronics
Hans Summers
Finally here's a full list of what I can order for you from Rapid
Electronics . Prices are the Rapid prices, i.e. no profit for G0UPL :-( Postage is the price of a UK 1st class stamp for UK orders (?0.28). Other countries will be extra at cost. You must tell me your orders by this Wednesday at 13:00 UK time (12:00 GMT). I will order on Wednesday from Rapid, receive the components on Thursday, and send them out to you on Thursday. UK orders should receive them on Friday, ready for the weekend's homebrewing! Don't send any money yet, just tell me what you want and then wait until Wednesday when I have placed the order at Rapid: it might become slightly cheaper still if we go over other quantity pricing thresholds. You can pay me by any of the following methods: 1. Paypal (preferred) to my email address. Anyone can use a credit card to pay me this way, without needing to be a PayPal member, see . 2. UK cheque or postal order 3. Cash: British Pounds, or if you like approximate equivalent amounts in US Dollar or Euro. Not other currencies please, I am a homebrewer not a bank, I can't handle Mauritanian Ouguiya or Azerbaijanian Manat. If you are going to pay by 2 or 3 above, then I will send you my postal address via email. Rapid do not stock 2N2218 driver transistors, nor are they at Farnell . However I have managed to find a different source for supply of 2N2219A which is like the 2N2218 but has better gain specification. I'm sure it will be suitable. So here's the prices and description: feel free to take all items or only those you think you need. To keep it simple, transistors will be in a set of 25 BC547B, and diodes in a set of 15 1N4148. This leaves a couple of transistors and diodes left over for later modifications! If there's anything else you need particularly then let me know. Varying the quantity is fine too, e.g. take two IRF510's so you have a spare if you are worried about frying them, or if you want to play with push-pull for higher output power. Prices are in UK pounds inclusive of VAT (sales tax). ?3.58 Qty 10 of 10.000 MHz crystals, HC49 style ?0.59 Qty 25 of BC547B transistors ?0.70 2N2219A driver transistor ?1.53 IRF510 MOSFET ?0.19 Qty 15 of 1N4148 diodes ?0.07 36V Zener diode ?0.05 9.1V Zener diode ?0.05 5.6V Zener diode ?0.29 LM386N-1 Audio Amp IC (correct variety) ?1.88 Qty 5 of 2-22pF trimmer capacitor ?0.71 Miniature tuning capacitor* ?9.92 total, if you wanted everything and including ?0.28 UK postage. * NOTE: The tuning capacitor is one of the miniature kind as used in portable radios. Size is 20.2 x 20.2 x 10.8mm. Control shaft is 6.6mm diameter tapped with 2.6mm thread. Panel mounting is via twwo 2.6mm tapped screws next to the control shaft. Capacitance: AM section 3.0 - 141.6pF, Oscillator section 4.0 - 59.2pF. So in parallel you'd have 200pF which is less than Farhan's design for 350pF. It might therefore be necessary to alter the VFO coil to get the required tuning range. 73 Hans G0UPL |
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Re: What are tap washers ?
ik1zyw
--- In BITX20@..., "Mark Jones" <Mark@H...> wrote:
Hi, just joined the group. Hope I will have some time to build this great RIG soon. Hmm, good question. An American asked me recently what a "jubileeclip" was - that was a struggle.water tap (faucet?) - like in the bathroom - so that when the water valve isUntil 10 minutes ago I never knew about "jubilee clips". Then I remembered our good friend Google has a good engine for searching images: Jubilee clip: Tap washer: Google images might help for other visual searches as well. Thanks for the explaination Mark, and sorry for the off-topic, Paolo |
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Re: Low output
Ashhar Farhan
On Mon, 21 Jun 2004, david.g3ryp wrote:
I've taken the measurements you suggested and indeed it was the driver whose output was low - only about 1 volt peak. I was using BC549s throughout and although they tested ok when I changed them in the pre-driver and driver stages for 2n2369s the output from the driver went up to 4.5volts peak. Now where does this 6.3 volt resistor fit in? Am I looking at the wrong schematic? Perhaps in the driver emitters? I'll try changing the 10 ohms to 5.6 or thereabouts and see if the output goes up.The driver and prediver's emitter resistors are 6.2ohms (i used 5 ohms). due to the feedback design, individual transistor types are non-critical. the driver did require a heavier than BC147/2N3904 type of transistor. The plastic package prevents one from being able to gauge their heating by just touching them. until they are properly cooked. the 2N3866 will do fine. the latest 'build' of the circuit is on www.phonestack.com/farhan. - farhan Lastly thanks for putting a unit on the rf voltages. All too often schematics either don't contain rf voltages at all or they don't specify whether they're Peak to Peak or Peak or RMS - and there's quite a difference! |
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Low output
david.g3ryp
开云体育Many thanks for the advice Farhan.
?
I've taken the measurements you suggested and
indeed it was the driver whose output was low - only about 1 volt peak. I was
using BC549s throughout and although they tested ok when I changed them in the
pre-driver and driver stages for 2n2369s the output from the driver went up to
4.5volts peak.
?
I've tried a variety of core types and none appears
to be critical. I'm using a t-50-6 in the IRF510 drain - 14 bifiliar turns to
get the 3uh you suggest. Know what you mean about winding these
things!
?
The output without the lpf in circuit is 6.25watts
but I need to adjust the bias for a standing current of rather more than 80ma to
achieve this - although it may be that the balanced mod is not that well
balanced (I haven't put in any caps yet).
I'll test this and let you know. Even without the
lpf the output is quite a pretty sine-wave.
?
Now where does this 6.3 volt resistor fit in? Am I
looking at the wrong schematic? Perhaps in the driver emitters? I'll try
changing the 10 ohms to 5.6 or thereabouts and see if the output goes
up.
?
Lastly thanks for putting a unit on the rf
voltages. All too often schematics either don't contain rf voltages at all or
they don't specify whether they're Peak to Peak or Peak or RMS - and there's
quite a difference!
?
I think I'll change the other 549s for 2n2369s if I
have enough just to see what happens.
?
Good luck to everyone.
?
David? |
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Use 2N3866 instead of 2N2218
Ashhar Farhan
the 2N2218 is a fatter type of 2N2222. you can use the 2N3866 instead.
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they are expensive in india. but they might be easier to find elsewhere. - farhan On Mon, 21 Jun 2004, Hans Summers wrote:
Rapid do not stock 2N2218 driver transistors, nor are they at Farnell |
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Re: Low Output (was Sunday)
ashhar_farhan
--- In BITX20@..., "david.g3ryp" <david.g3ryp@n...>
wrote: I wonder how much output everyone's getting from the IRF510?with the lpf in circuit. I've checked the lpf cut-off and I would expect some attenuation but not that much. I tried an irf530 which promptly overheated and destroyed itself as I increased the bias! hehe, david worry not. there are a couple of things that you ought to check. 1) cut the supply to the IRF510. then measure the RF output of the driver at 50 ohms resistors across the RIF510's gate. it should show 5 volts peak (that is 10 volts between the +ve and -ve swing). If you not are getting that much, then you have probably wired the output transformer incorrectly. they are probably in parallel to each other, or worse, the drain and the power supply are connected to the separate ends of the winding. check it carefully. 2) if you are not getting 5 volts at the 50 ohms resistor across the IRF510, then measure the output from the predriver. it should be a more than one volt peak (2 volts peak to peak on the 'scope). if either of these is a problem. check the following: a)that the collectors are showing somewhere north of 10 volts and the emitters are showing about 2 volts on both the driver and the predriver. b)if the DC voltages are alright, suspect that the AC connections are a problem. Most probably it is a mis-wired transformer. take them out of the circuit and check them carefully. i frequently make a mistake with shorting the opposite ends of the SAME wire and leaving the other wire in the pair isolated.d c) the 6.3 ohms, in my case is approximated by paralleling two 10 ohms. check that the 10 ohms IS 10 ohms and not 100 ohms. it is easy to confuse brown-black-brown with brown-black-black. above all, trace! measure the outputs at the RF fitler, pre-driver and the PA. tell us how much you get at each point. we will 'divide and conquer'. i dont know if i mentioned in the article that you should set the drain current to between 50 and 80mAs. I set it at 80mA, a bit on the higher side, but the linearity is better. - farhan |
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Re: Substitutions or Sourcing components
Jon Harris
Thanks Hans, and many thanks for the offer of help, much
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appreciated! 73, Jon H. ----- Original Message -----
From: "Hans Summers" <Hans.Summers@...> To: <BITX20@...> Sent: Sunday, June 20, 2004 10:28 AM Subject: Re: [BITX20] Substitutions or Sourcing components Jon, I'll send you an email tomorrow with final details. 72/3 de Hans G0UPL -----Original Message----- From: Jon Harris <jon@...> To: BITX20@... <BITX20@...> Sent: Sat Jun 19 22:25:36 2004 Subject: Re: [BITX20] Substitutions or Sourcing components Sign me up too Hans, where do i send the cash! Cheers, Jon H. ----- Original Message ----- From: "Mark Jones" <Mark@...> To: <BITX20@...> Sent: Saturday, June 19, 2004 8:26 AM Subject: RE: [BITX20] Substitutions or Sourcing components Hi Hans Happy to go for a 6.21 order from you! Regards, Mark G0MGX -----Original Message----- From: Hans Summers [mailto:Hans.Summers@...] Sent: 18 June 2004 11:56 To: 'BITX20@...' Subject: RE: [BITX20] Substitutions or Sourcing components Keytronics has 10MHz xtals at ???1.00 each (ten required)I'm confused about the 2N3866 - what's it for? I see no mention on the circuit diagram; the nice thing is that a variety of transistors will do in this design. Rapid Electronics () sell 10MHz crystals at ???0.38 each (???0.45 incl sales tax). That drops to ???0.305 (???0.36 incl VAT) for QTY 25+. If enough people want them I'd be happy to order a batch and parcel them out. People who are interested in 10, let me know within the next few days and maybe we'll sort it out sometime next week. Assuming 25+, the price would be ???3.86 for 10 including a 1st class UK postage stamp (overseas postage stamp, extra). Ok look, I'm not going into the kit business but while we're at it, if you want them (also from Rapid): 25 BC547B's suitable for the rig: ???0.82 incl VAT 1 IRF510: ???1.53 incl VAT Presumably the total weight will be under 60g so these will all fit under the same single ???0.28 postage stamp. So, for a LIMITED TIME ONLY... Crystals, transistors and the MOSFET, ???6.21 incl UK postage (overseas is fine, we just add the extra postage). 72/3 Hans G0UPL Yahoo! Groups Sponsor ADVERTISEMENT < 001176/D=gr oups/S=1705063108:HM/EXP=1087642550/A=2128215/R=0/SIG=10se96mf6/* anion.yahoo.com> click here < D=groups/S= :HM/A=2128215/rand=403314333> _____ Yahoo! Groups Links * To visit your group on the web, go to: * To unsubscribe from this group, send an email to: BITX20-unsubscribe@... <mailto:BITX20-unsubscribe@...?subject=Unsubscribe> * Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service <> . Yahoo! Groups Links Yahoo! Groups Sponsor ADVERTISEMENT ----------------------------------------------------------------- --------------- Yahoo! Groups Links a.. To visit your group on the web, go to: b.. To unsubscribe from this group, send an email to: BITX20-unsubscribe@... c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. |
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