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Wednesday, 31 December 2008

Trio of LF SDR RX, first for all the HF bands

Just had fun building these three Softrock v6.2 lite SDR RX ready for operations in New Year.

(Images to follow)
136kHz


500kHz


160m


They will go into a single chassis along with other bands.

I bought a Delta 1010 LT which is a 10 input 10 output PCI sound card earlier in 2007 and will look at creating an all band SDR RX with it.

Wednesday, 24 December 2008

Another batch of PCB etched



As did all the shopping etc for xmas happy to put my feet up. And whilst doing that made up some new etch and used a new digital thermometer to check the bath is at 50 degrees C. The etch was really fast this time.

Just finished drying off the latest batch of PCB and what I especially like is no yellow/brown stains on everything. The solution turns a little blue/green, probably from the marker /cd pen I used. The boards are naturally yellow/green

These are top left; a N3ZI LCD display controller boards, top right; a Freakin' Beacon controller, bottom left; KD1JV (see earlier post) and botton right; one of the RD16HHF1 Mosfet PA boards (sea earlier post).

Whilst waiting for the etch I melted a little solder for a couple of N6BM projects, the Miniboots II PA and an LC Meter. The LC meter design is actually from MARC http://www.marc.org.au/index.html VK3BHR LC Meter Project - Mk.II but Wayne had reworked the PCB layout. I have a nice desktop calculator style case that one will go into.

Tuesday, 23 December 2008

KD1JV and N7VE Battery Monitors

As I operate /P from time to time using a battery monitor is always a good idea. Right now I use a small digital multi meter from Conrad (Friedricshafen 2007) but I can see the benfit of fitting one of these to a rig.
There was bit of a post the other day on qrp-l for the battery monitor from qrpkits (N7VE) Dan Tayloe and the one from (KD1JV) Steve Weber was also mentioned. Well I have put together a couple of PCB for both with the same sized PCB. There are a few differences in that one requires tracks on both sides. One uses a 7805 as a voltage reference the other uses a 3.3V zener diode. I have some 431CP voltage reference semi conductors and I will try one of those as well if the other option is not accurate enough.
As I will homebrew them I will use components I have.
N7VE


KD1JV





N3ZI LCD Display

Building the N3ZI LCD Digital Display and making up PCB. for it.

RD16HHF1 MOSFET



Hi,
At FDIM 2008 I had a few chats over lunch with Ted Bruce editor at QQ who later sent me a couple of these MOSFET and I said I'd work them into a little qrp amp of some sort. (And write it up for QQ of course!).
Here are some preliminary images of the PCB fabrication after the ugly looking prototype worked.
The production method uses press n peel blue film (glossy photo paper also works) and an iron on transfer to PCB before etching. So using Express PCB (www.expressspcb.com) I create a PCB layout. Print it out onto paper and cut out the layout. Then tape a square of Blue Press n' Peel film onto the reverse of the paper where the layout has been cut out.



I am playing with output transformers so I have used either T106 or a pair of stacked BN43-202 or BN43-202 on the PCB hence the complicated component layout, but no extra tracks or holes. The T106 or BN43-302 or 202 were picked up from W8DIZ at FDIM but you can order online from him at http://www.kitsandparts.com


Feed it into the laser printer:



And hey presto one PCB mask for transfering onto a fresh piece of PCB.

Expecting to get some time in the shack this Xmas I have pre made up these boards and a few others so I can make a fresh batch of etch and take that down with me.

The PCB will be about 2" square. Note there are NO LPF components fitted to this PCB they will be needed. The populated PCB will be fitted onto the lid of a Jack Daniels minature tin and I am using a 1U solid copper PC CPU heatsink and fan for cooling. The RD16HHF1 will be mounted under the board.

Thursday, 11 December 2008

QRP /P operation PSK31 from beach

Not all /P operation M1KTA does on a beach is from some tropical DX paradise unfortunately. I braved the cold from a beach on the North Sea coast using a homebrew expedition tent I made a while back. The tent is self supporting and also contains a sling running through the tent wall to tie into ice screws etc when in the mountains on steep snow slopes.

It took 1/2 day to cycle there, and after realising had forgotten the SLA battery... oops, fortunately found a cafe that had a box of rather old sun bleached packets of AA batteries I bought for £1.

Operation into a buddipole from FT817 with psk31 0.5W running using only the old batteries with a VERY OLD Dell laptop whilst the batteries lasted. It was light enough to operate inside the tent but brrrr... it was cold.

This was the same place where I operated from and sent a message to GQRP about the sea wall effect so thought I'd try it again.



Just checking where the tide is.


Arty shot.


The bottom of the tent is a red fabric and there is plenty of room to sit and operate sitting up.



When the door is zipped up (There is a vent in two walls I can close from inside) the tent is wind and water proof.

Tuesday, 9 December 2008

LF Operations

Having just put the LF antennas up again and got the shack prepared for evening/night time operating over this xmas I (M1KTA) will attempt some 137kHz operation CW and QRSS and I expect will work some cross band 500kHz-80m CW.

Hope to meet you on the bands.

72

Dom
M1KTA
Loc: JO02bd

Wednesday, 26 November 2008

MKARS 80m tcvr


Bought a kit at Leicester Rally and will be a kit for Xmas holidays.


The reverse tuning is a bit odd which is probably what interested me.


As my QTH is only c40 miles East of MKARS/Betchley Park I expect I might visit once operational.


I took all the parts out once arrived home, before dutifully putting it into one of the clear boxes I use for storing build projects in the shack. So far I can see I might experiment with a slightly larger case using an air spaced variable (another Leicester purchase) and a reduction drive for tuning or might try the varicap mod with a 10 turn pot (bought a whole box of various values both recycled and new at GQRP rally), definitely will add an in case battery holder which will also be used by rechargable batteries, a little L match ATU so self contained for /P http://m1kta-qrp.blogspot.com/2008/09/what-to-do-with-1-pole-12-way-switch.html, I find the W3EDP antenna works well for 80m and finally will have to paint it some luminous/gawdy colour scheme so a trip to B&Q to see what colour spray enamel paints are available is needed.


After spending last year in HB9 I discovered the benfit of using lock 'n' lock boxes for homebrew in cold & wet /P conditions so might investigate using one possibly as the enclosure not just transport in a rucksack/bicycle pannier.

Thursday, 20 November 2008

TA7358


Bit of an abscence for almost a month.... reason is I had a job/work to do so radio took a back seat for a bit.

Just picked up on the discussions about using the TA7358 as an alternative to the SE/NE602 as a mixer which I am all in favour of as the 602 are becoming very expensive.

Ordered a number from Peter at Jabdog and once they arrive will start to look at them in circuits.

One advanced option is here:
http://shipwreck.yi.org/documents/projects/homebrew/vu2hmy_HMY2K8_All_Band_SSB-CW_XCVR.pdf
another:
http://forum.cqham.ru/download.php?id=2652.



The text in Russian is:



Приемник прямого преобразования для диапазона 7MHz
Cosy MUTO, JH5ESM (вольный перевод Валерия, RW3DKB)

Введение.
Этот приемник - разработка для Технического Симпозиума ARRL 1999г в Кагава (Япония). Входная ИС используется для формирования внешних цепей FM-приемников и содержит каскады УВЧ/смеситель/гетеродин. Для питания достаточно 3 вольт - только 2 батарейки типа АА.
Описание Схемы.
Рис. 1 показывает оригинальную схематику приемника.
Рис.1 Оригинальная схематика приемника.

Микросхема TA7358AP содержит в себе все входные каскады для FM приемника в одном корпусе. Ножки с 1 по 3 - это цепи каскада УВЧ, с 4 по 6 - это цепи двойного балансного смесителя Гилберта (Gilbert DBM cell) и с 7 по 9 - выводы транзистора гетеродина.
Полный диапазон приемника оценен как 90dB. Дополнительный звуковой усилитель потребовался для получения громкоговорящего приема.
Звуковые Колебания.
Возникают паразитные звуковые эффекты, когда Вы делаете громче регулятор громкости. Это вызвано обратной связью через линию питания. Для их устранения необходимо модернизировать схему. В частности ввести в нее развязывающие цепочки по питанию каскадов.
Переделанная схема представлена на Рис.2.

Примечание.
Если напряжение постоянного тока через резистор 1 кОм больше чем 0.6 V, его номинал должен быть уменьшен, чтобы избежать запирания внутренних диодов в TA7358.



The English translation is:



Direct conversion receiver for the band 7MHz Cosy MUTO, JH5ESM (loose translation of Valery, RW3DKB) Introduction. This receiver - development for the Technical Symposium ARRL 1999 in Kagawa (Japan). Home IS used to form external circuits FM-receivers and contains cascades UHF / mixer / oscillator. For a 3-volt power supply - only 2 batteries type AA. Description of the Scheme. Fig. 1 shows the original shematiku receiver. Fig.1 The original shematika receiver. TA7358AP chip contains all the input cascades to the FM receiver in one case. Motor from 1 to 3 - this cascade of UHF supply chain, from 4 to 6 - this chain of double balanced mixer Gilbert (Gilbert DBM cell) and from 7 to 9 - the findings of transistors heterodyne. Full range of the receiver rated as 90dB. Additional audio amplifier required to obtain loudspeaker reception. Sound Fluctuations. There parasitic sound effects when you make a louder volume. This is due to feedback through the power line. To eliminate the need to modernize the scheme. In particular, to enter into it razvyazyvayuschie chain of food cascades. Reworked diagram Pic.2 represented at. Note. If the voltage constant current through the resistor 1 kOhm more than 0.6 V, its face value should be reduced to avoid locking the internal diodes in TA7358.

Thursday, 23 October 2008

Cobweb

Following on from http://m1kta-qrp.blogspot.com/2008/10/new-antenna-at-qth.html

Portable Cobweb:

Found a centre at GQRP rally last w/e, go to http://www.amtoolsuk.com/ANTENNAPLATECP1PAGE.html for the details and read the drilling instructions.

The centre unit is designed for 20mm conduit so for the cobweb 10m-20m you need poles 6' 6" long the poles I have are 4m poles from sky blue. The centre 2 sections are exactly 20mm at the base so I will use the centre two sections only. So will 'store the base and whip sections for something else. You could use thick walled 20mm conduit tubing, with some 'sag'.

The great thing about the centre plate is the option of use of the 4 pole 90 degree options for all sorts of antennas. Not just a cobweb, I can see a wire beam as per spider beam should be possible as well.

Wednesday, 22 October 2008

Adding bands to my repaired vertical

A tree at bottom of garden about 6 weeks or so ago a branch came down and took out my vertical. I obtained a new Ali pole and put it in place so the Hustler 6BTV vertical is back up and running again (managed a QRPp 80m qso with G3XBM with it yesterday).

Anyway thinking time I need to add WARC bands 17m and 12m to it.

Saw the add on kits at Dayton FDIM but serious costs involved so this is how I will do it (direct copy from AD5TH):

Parts Required
1. 25ft - Multi strand insulated copper wire (just wired up green house so spare lengths)
2. 2 - ring terminals (crimp or solder)
3. 4 - plexiglass spreader arms (home brew)

One of the home brew "spreader" arms



Spreader Arms

Clive (M5CHH) had given me a small piece of plexiglass a while back. You need a piece 14 inch x 8 inch and about 1/4 inch thick. The alternative is you could use ply wood and paint or varnish it.
1. Cut plexiglass into 14 inch long by 2 inch wide strips (use band saw or score and snap)
2. Drill a single 1 1/4" hole in center on each strip. Drill very carefully.
3. Drill a single 1/8 " hole on center 1 inch from each end of strip. 2 holes per strip (1 on each end)

Vertical Radiators
1. From 25 ft of wire cut 2 lengths 14ft (17M) and 10 ft (12M)
2. Strip one end of each and attach crimp or soldered ring terminal

Assembly

1. Disassemble your Hustler antenna and place a plexiglass spreader over the main tube at the very bottom right above the base and then place a spreader on top of the 10M trap and another on top of the 15M trap. The fourth and final spreader is installed at the bottom of the 20M trap supported by a plastic tie around the antenna tube directly beneath the spreader. Reassemble the antenna and test for proper operation on original 10/15/20/40/80M bands
2. Attach both 12M and 17M wire ring terminals to the main feedpoint.
3. Thread the 12M and 17M wires through the 1/8 inch hole in each spreader. The spreader on top of the 10M trap needs to be slid up the main antenna tube about half way towards the 15M trap and held with a plastic tie. This locates the spreader properly to intersect the upper portion of the 12M vertical radiator
4. Temporarily secure the other end of each wire with a plastic tie or folding the wire over it's top most spreader.
5. Check the VSWR and trim to resonance for 12M and 17M. Secure wires to spreaders with plastic ties.
6. Typically after 12M and 17M are tuned you'll need to re-tune one or two of the other bands of the Hustler BTV

AD5TH 5-BTV 10M and 20M needed a retune. 15M 40M and 80M VSWR was unchanged after the modification.

7. These photos are from AD5TH. I will add mine shortly.




Some notes:
1. I keep meaning to purchase/make a tilt over mount for my 6-BTV, AD5TH said this would have really helped throughout the procedure. It is more cumbersome to complete this modification without the aid of a tilt over mount. An alternative is to enlist the assistance of a helper and a ladder.
2. The wire lengths cited in the instructions are longer than needed by design so simply prudent trimming and testing will achieve resonance. It took AD5TH only 3 trim and test cycles to get both 12M and 17M flat.
3. If your Hustler is ground mounted without any buried radials it is highly recommended that you add at least 25 or 30 ground radials at least 15 ft in length each. Radials in soil need not be "tuned" as "in-the-air" radials must be. At M1KTA QTH I have a lot of random lengths burried around the base of the vertical along with a couple of 4 foot ground rods, the water table is also very high.
4. AD5TH suggested with the 5BTV 20M can be stubborn and needed to be shortened but was already shortened to the max. So with the 6BTV I might have to add a capacitive hat to 20m (I have made one before for use with a buddipole on 160m! which is 3 18" lengths of coat hanger wire at 120 degrees separation perpendicualr to the mast which will raise the resonant frequency). AD5TH was then able to adjust 20m.

As I am doing an antenna 'shoot off' especially as I bought a centre for the HEx beam/cobweb at GQRP rally this will be my 'reference antenna'.

The orginal AD5TH website seems to have gone. These were the original instructions:

Parts Required
25ft - #12 insulated copper wire - (about $4)
ring terminals (crimp or solder) - (about $1)
plexiglass spreader arms (home brew) - (about $5)

Home brew "spreader" drawing

Spreader Arms
Required stock 14 inch x 8 inch 1/4 inch thick plexiglass (about $5 cost)
Cut plexiglass into 14 inch long by 2 inch wide strips (use band saw or score and snap)
Drill a single 1&1/4 inch hole in center on each strip. Use 1 1/4 inch hole saw. Drill very carefully.
Drill a single 1/8 inch hole on center 1 inch from each end of strip. 2 holes per strip (1 on each end)

Vertical Radiators
From 25 ft of #12 wire cut 2 lengths 14ft (17M) and 10 ft (12M)
Strip one end of each and attach crimp or soldered ring terminal

Assembly
Disassemble your Hustler antenna and place a plexiglass spreader over the main tube at the very bottom right above the base and then place a spreader on top of the 10M trap and another on top of the 15M trap. The fourth and final spreader is installed at the bottom of the 20M trap supported by a plastic tie around the antenna tube directly beneath the spreader. Reassemble the antenna and test for proper operation on original 10/15/20/40/80M bands if 5-BTV. Likewise if 4-BTV or 6-BTV check on all original bands for proper operation after reassembly.

Attach both 12M and 17M wire ring terminals to the main feedpoint.
Thread the 12M and 17M wires through the 1/8 inch hole in each spreader. The spreader on top of the 10M trap needs to be slid up the main antenna tube about half way towards the 15M trap and held with a plastic tie. This locates the spreader properly to intersect the upper portion of the12M vertical radiator
Temporarily secure the other end of each wire with a plastic tie or folding the wire over it's top most spreader.
Check the VSWR and trim to resonance for 12M and 17M. Secure wires to spreaders with plastic ties.
Typically after 12M and 17M are tuned you'll need to re-tune one or two of the other bands of the Hustler BTV. On my 5-BTV 10M and 20M needed a retune. 15M 40M and 80M VSWR was unchanged after the modification.

I have a tilt-over mount on my 5-BTV so this really helped throughout the procedure. It is more cumbersome to complete this modification without the aid of a tilt over mount. An alternative is to enlist the assistance of a helper.
The wire lengths cited in the instructions are longer than needed by design so simply prudent trimming and testing will achieve resonance. It took me only 3 trim and test cycles to get both 12M and 17M flat.
If your Hustler is ground mounted without any buried radials it is highly recommended that you add at least 25 or 30 ground radials at least 15 ft in length each. Radials in soil need not be "tuned" as "in-the-air" radials must be.
Today I completed retuning 20M and 10M. Now ALL 7 bands are under 1.3:1. 20M was stubborn and needed to be shortened but was already shortened to the max. I raised the 20M capacitive hat about 1 1/2 " which predictably raised the resonant frequency. I was then able to routinely lengthen the 20M adjustment and the match fell right in.

GQRP convention

My talk, everyone got a snooze for an hour at least....

QRPp Cat in QSO with M1KTA at GQRP hotel


Jan (G0BBL), Alan (M0PUB) and Klaus


The top table... Ken, Graham, Dick Pascoe, Tony, George...



Nick and XYL in front (M0NJP/ON4NIC), Clive (M5CHH) on right, Me (M1KTA) on left

Formers for winding inductors

On the way back from GQRP Mini convention we stopped off in a couple of service stations and to the probable puzzlement of the travelling companions Henning and Clive I collected a few items each time.

Back in the shack I have started to look at different coil formers for use in homebrew so will add them to the ones I already have.



From left to right they are straws from Burger King, Starbucks, Costa Coffee and wooden stirrers from Little Chef. The largest is the Starbucks clear straw.

More info to be updated after testing.

Mobile Phone

Time to update the mobile phone and add a ring tone.... So fed up with the sound following a text messages of "SMS" for the ring tones so created my own:

http://www.planetofnoise.com/midi/morse2mid.php

Tuesday, 21 October 2008

Thursday, 16 October 2008

GQRP-Rishworth 2008

I am one of those giving a talk this year.


The agenda email from Graham....


Hi,

Here is a list of the speakers and their subjects at Rishworth this coming Saturday:

11.00 : Software Defined Radio For Home Construction

Alan M0PUB and Jan G0BBL will present recent developments from the popular Softrock kits to the new QRP2008 transceiver Project. They will also cover the trend towards "Direct to All Digital".

13.00 : "Alpine style" DXpeditions VE3-7/, HB9/, HB0/ and 3B8/Dominic Baines, M1KTA

M1KTA in Alps 2003

"Alpine Style" is a reference to mountaineering, back in early 20th Century the big mountains of the world were conquered by huge expeditions over many months with huge teams. Climbers now carry everything they needed"Alpine Style" and move self contained using whatever they had with them or found.

14.00 : Antenna for Limited SpacesColin Turner, G3VTT

Colin writes the popular SPRAT feature AAA (Antennas, Awards, and Anecdotes)and offers practical ideas for the operator who has to cope with limitedspace for antennas.

15.00 : Life is Too Short for QRO

George Dobbs, G3RJVA little QRP philosophy and a few practical ideas. George is standing infor Rob Mannion of PW, who sadly cannot join us but sends everyone hisgreetings.

16.00: Open Technical Forum with David Stockton, GM4ZNX

A regular at the convention, David applies his flexible technical mind tosubjects suggested by your questions. You ask the questions and David provides his explanations. David enjoys active questioning from the audience, at all levels, so do not be afraid to ask him to pitch his explanations to your level.
See you all there?
72/3GrahamG3MFJ

Monday, 13 October 2008

Determining meter parameters ... 1964 style






How many times have you bought a junk meter or salvaged a meter (like I did just before w/e) from some old bit of kit only to find there are no markings or worse the scale is bespoke, nothing to do with mA or V or worse apparently depended on some parts that are no longer connected.
Probably old hat to any that know, to those that don't/didn't like me maybe this might be of use:
Going through a box of old magaznes found an article from 1964 about just this subject. Then I saw the circuit and thought there has to be something missing but there wasn't so I tried it and it works.
The circuit as you see above is so simple.

The process to use it is not that hard either (from the article page 33 by K5SOD):

I will post images of the build and test steps, I used 4mm banana jack/binding posts from Maplin at AB, CD and EF. The article says you need two potentiometers, R1 (1K) and R2 (200k) the ones I used are 1K and 250K that happened to be in my junk box at the time. The article states that potentiometer with similar values can be substituted, and linear pots are best. I salvaged a couple of dual AA batery holders and used them and a couple of rechargable batteries.


It takes longer to tell about how to use this than to actually perform measurements. Once you have been through the process a couple of times, it only takes a couple of minutes to fully investigate a meters characteristics.

What you do need is a meter with known characteristics and I used a good old elcheapo DVM from my collection (10 for £2) and it has some small amp meter ranges, to use with really small scale meters you might need something better. I suspect an analogue meter will work just as well.

Let’s assume that you know absolutely nothing about your “unknown" meter which is usually a safe place to start.

Place the unknown meter between C and D, The orientation needs to be so that positive voltage applied makes the meter move, most normal meters that means the positive lead connects to C. I have a couple of centre zero meters as well so the connection could be either way. With the battery connected select full scale on the switch position.

Rotate R1 for maximum resistance. Many pots have maximum resistance (which will be minimum current) when the control is fully CCW, but the direction of travel is arbitrary and unimportant. The important thing is to be sure it is set for minimum current to start the test.

If you have it set your DVM to read 200 mA, or more, then insert it into the circuit with positive lead to B and negative lead to A. Always start with a high current setting on your DVM and work down.

You may see absolutely nothing on the meter, adjust R1 (reducing it) to obtain a full scale reading on the unknown meter by reducing the resistance. If a full-scale reading cannot be obtained with R1 set for minimum resistance, the unknown meter is beyond the current supply capabilities of the batteries. In such an event, disconnect the DVM quickly to prevent draining your batteries. This condition is probably due to an internal shunt in the unknown meter. This can be overcome as will be explained, later.

If you have a full-scale deflection on the unknown meter, but there is little or no reading on your DVM, set the DVM switch to read less and less current until you obtain a reading for the full-scale current on the meter under test. If you cannot get a low enough scale you need to find another known meter. Remember you could get there using another 'unknown/now known meter' with a small enough scale!

Anyway when the unknown meter is a FSD after adjusting R1 the THE CURRENT READING YOU SEE ON YOUR DVM IS THE FULL SCALE CURRENT OF YOUR (formerly) UNKNOWN METER. Easy isn't it?


As I was wanting to use mine as an audio level S meter for the Norcal-20 O built (maybe a good idea?) I wanted a meter with FSD of between 100uA and 500uA. The first meter I tested has a full deflection current of 200 uA.

Now before you do anything else adjust R1 for approximately 1/2 full scale, then disconnect the DVM.

Replace the DMM with a jumper between A and B. If like me you use banana plugs this is made easier with a short 4mm to 4mm lead.


Now re-adjust R1 for a full scale reading.


Change the S1 to Half Scale and adjust R2 for a half scale reading.

Set S1 back to Full Scale, and measure the internal resistance between E and F with your DVM.


YOU NOW KNOW THE INTERNAL RESISTANCE OF YOUR (formerly) UNKNOWN METER.

For this example, assume the internal resistance is 200 Ohms.

Your "unknown" meter is now very much known.


Makes sure the DVM battery is not low otherwise your measurements may be out.


I'll update the complications for meters where there is a very high internal resistance for a meter.



IF METER IS BEYOND MEASURING SCALE:


If a full-scale reading cannot be obtained with R1 set for minimum resistance, the unknown meter is beyond the current supplying capabilities of the batteries. That this condition was probably caused by a shunt being built into the meter. For example, a meter that has a scale indicating it measures up to 10 Amps, it may have an internal shunt already simply because most meters are built to measure 1 mA, or less if no shunt resistor is used.
Given that you are salvaging a meter, the next stage should not be a problem, surgery is required. That is, you must open the meter and remove the built-in shunt, then proceed as you would with a "normal" meter. The internal components are mechanically very delicate, similar to the insides of a mechanical watch. So, if you have the patience and dedication required to disassemble the meter, remove the shunt, re-assemble the meter and perform the Meter Master investigation as described above, you can salvage most any meter. Some are very easy to get into some seem to be sealed within plastic, your milage may vary and may not always be successful, but it will be a satisfying end if you are so inclined. If not, its best to simply toss the meter into the nearest trash can and forget about it.

One piece if kit contained these meters: (images to come):

Friday, 10 October 2008

Norcal-2030









Finally made it into Cambridge this morning so visted the Royal Mail collection depot as I have had an item that came through customs to pay for and collect what on earth is it?













Ah the Norcal 2030 partial kit ordered a while ago.




So as I am sure everyone knows this rig is 20m or 30m and mostly surface mount components with a few through hole. The board is going to be pretty full.




So time to print off the parts list and see what I have missing still.


I know LT samples can be obtained for the LT chips (saves some costs!)



Think a 30m rig might be needed.



Here are some notes on parts:


Digikey:



email exchange I just had:
----- Original Message ----
From: John ******
Sent: Monday, 27 April, 2009 20:20:01
Subject: NorCal 2030 question
Dominic,I ran across your blog entry about the build of the NorCal 2030 partial kit. I'm trying to get the parts together for the build and was wondering if you could offer some assistance.I can't figure out what type of part to order (from Mouser or DigiKey) for these parts:
1 Power Jack
1 SPST miniture toggle
2 Sub-mini Push button
Would you mind letting me know what you ordered?Also, what are you planning on doing to finish the case on the radio?
Best 73-john W4PAH
Reply:
Hi John,
Not done much on it since buying the partial kit and filling the component bags ready to build however... V5 of the manual...
1. Power jack. Page 91 shows their leads just coming out of the enclosure. JP2, Is just a set of leads. I use 2.5mm barrel connectors almost across the board for power so will just drill a 8mm hole if not there and fit the jack. I have also seen some use Anderson power poles as a pig tail and even just a grommet and a DC lead...
2. SPST minature toggle and 3. minature push buttons. There are two of each.
2 First is just one off so anything that can handle the current, or don't bother and jumper it and use the dc connector? The other is front panel (first image one labelled SPOT) S1 for RIT/XIT control so could be almost anything. Connections just to left of "N7SE" silk screen bottom left of board top. Page 2 of the schematic top left.
3 are for keyer command (S3) top right and AFA (S2) (just right of centre of board left of IC1) you cannot see the connection on the board photos. Manual Page 46 fig 44. Page 4 of the schematic. Again clearly on front panel, look at manual images.They are push to make, monentary.
72
Dom
M1KTA

Thursday, 9 October 2008

Norcal Power Meter

Following on from a post on QRP-L I recieved this kit 24th June and proceeded to build it within days day following the 1C version of the instructions, especially watching the polarity of D3 and D4 and D1 and D2 but the meter exhibits some very wierd behaviour.

On power on the meter, with no RF connections states F:1.4W R:1.4W SWR:9.9 and the analogue meter reads hard over FSD. Or the R (reverse) jumps about and so does the SWR and the meter bounces to FSD (see the video clip).

video

I first thought it might have been the battery so I changed that but no change in behaviour.

I put it down to making a basic error somewhere and thought nothing more of it and thought would return to look at this later when another on the QRP-L list posted a similar problem. So thought perhaps wasn't just me.

As I built it, you can see there isn't much to it, but see if you can spot the problem before you look at the solution lower down the post?

















THE SOLUTION:

The problem was D3 and D4.




I should have read the schematic and used the brain cells!
It should look like this:




I removed the IN5711 provided and used a matched pair of 1N5711 (red and black not blue and black diodes in above pictures), and the circuit now works exactly as it should.
As Bruce N1RX said in an email... "You put the diodes in opposite from the pictures in the manual. By that, I mean you put the end closest to the board in the opposite hole, but you had the -polarity- of the diode reversed from what it should be. The revised instructions are correct IF you bend the leads so that the band is facing UP as in the pictures. You have the bands 'facing down'. Use your schematic. The cathode (banded end) of D3 should be connected to pin 6 of U3. The cathode (banded end of D4 should be connected to pin 2 of> U3."

Oops!