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Archive for April, 2015

M0CVO Amateur Radio Antics The story continues..

Well, the TS-780 arrived, well packed in a Yaesu-Musen FT-221 box.  A really nice solid unit weighing in at a straight 10.1kg (22.2lb).  I took it out of the box and was pleased to see that it came with the 220v mains cable and not the 13.8VDC plug.  So I plugged it in and attached antennas to the two sockets on the rear of the case – a SO239 socket for the 145MHz antenna and a N socket for the 430MHz antenna. Plugged it in, turned it on and powered it up.  Well the lights came on but it was not showing the frequency on the front panel, nor were any of the other features operational.  Not wishing to panic I just left it for a while, still running and went to see if I could locate a full set of instructions and a service manual, yes, that’s right, there was none included with the radio.  I contacted Kenwood UK via their twitter account and Mark Haynes, M0DXR, the area sales manager, got back to me with both manuals that he e-mailed to me in PDF format.

CDwDWoAW8AA94Uv The TS-780 out of the box..

Returning to the radio I noted that it had fully come to life, displaying frequency correctly and being fully functional.  It isn’t a valved set but it still needed 5 minutes to warm up, it is an old set (1983) after all.  So I got my FT-232 handy (2m) and switched it to low power, set it on 145.425 and set the TS-780 to the same and tried them out both ways (1Watt only).  All working well.  Also tried the same on 70cm using my IC-E80 as the second set.  This working fine also.  I switched it to 144.300MHz, USB, and spent some time listening.  Obviously, on a Wednesday afternoon I wasn’t expecting to hear much but suddenly, out of the blue, a voice was heard, G4BZA was answering a call that I couldn’t hear.  Anyway, I followed them up to 144.305MHz and listened for a while.  Absolutely crystal clear RX and so much better sounding than on my modern FT-817, much less white noise.  I checked for distance and he is north of Horncastle in a village closer to Louth.  Not bad from my restricted location!  I also managed a short QSO with M1AIE/m on 2m FM but he was travelling away from me and lost me when he passed through Barkston Heath, a RAF base about 5 miles from here.

Then I started to source the issues with the radio.  The battery holder for the backup and memory storage was in pieces and crudely held with some cable ties.  Obviously this needed replacing as some of the contacts were missing.  This is to hold three AA batteries.  Secondly, the TX power couldn’t be increased on 2m above 1.5W so this needed looking into also.  The seller told me that on 70cm it was 5kHz out but on testing this it seemed alright so not an issue.

CD1UwiJWIAAmNhE Working happily on 70cm

So, day 2 and I opened the case up.  First thing I did was replace the battery holder.  Not difficult, just a five minute job.  Next task was to try and get the power levels up on 2m.  I consulted the manuals and checked the associated components leading up to the final PA.  All seemed fine so I assumed that the PA must be at fault.  the unit in question is 57713, a 144 -148MHz linear amplifier capable of giving 30W.  However, when I try to source them I discovered that they are no longer in production (what a surprise).  I contacted Kenwood again and they informed me that they had some left in Japan and gave me a number to call.  However, when I called, for a single unit it would cost me £88 with a 3 – 4 week wait for delivery.

CD1viamW0AAhLk_ Inside the beast

I recalled that the seller was also selling a 1kW linear for 2m and wondered if the owner of the TS-780 had adjusted the bias in any way to reduce the drive for this reason.  Back to the service manual and, leafing through the pages I noted that there was a way that this could be achieved.  Turning the unit upside down to access the final stages for 144MHz I located VR1, VR2 and VR3. Admittedly I needed a torch to see them crammed in at the back. Anyway, VR2 was bent towards the board showing that a screwdriver had been pushed in sometime.  Anyway, the voltage at L15 was less than the 0.5V that it should have been and the TX power was only 1.5W (CW).  I used a plastic hook to raise VR1 back up and then used a plastic trimming tool to rotate VR1 in a clockwise direction.  The power gradually came up and am now happy.  More tests will be undertaken in due course.

CD16bHTWAAAtYHt On 145MHz, TX.

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M0CVO Amateur Radio Antics The story continues

You may recall that previously I spoke of a kit that arrived from China with no instructions and a parts list written mostly in Chinese.  This was for a 3.5W version of the 49er transceiver.

The receiver section was based around the NE602 AM receiver IC (8 pin DIL) with a 7.023MHz crystal to set the frequency and a diode ring as a demodulator (2 * 1N4148 diodes).  This then fed into an LM386 audio amplifier and associated circuitry.

TR switching is achieved by keying the buffer amp made up of Q2 (an 8050) and Q3 (an 8550).  This then provides a feedback loop through oscillator B and oscillator E through pin 7 and pin 8 on the NE602.  This then turns on Q6 (an 8050) to provide the base voltage for the final – a D882 NPN.  This then feeds into a band pass filter ( a pi filter made up of L4, 16 turns on a T37-2, C17 (470p) and C18 (470p)) and then to the antenna.

49er completed.

As can be seen from the image it is a rather crowded board.  I must now design a box for it as it is a little too large to fit inside my Altoids / Strong mints tin.  Will probably construct one from scrap copper clad PCB.

I have also found out that the TS-780 should arrive on Thursday so that will be something to look forward to as I test it out and refurbish it.

M0CVO Amateur Radio Antics

April 26, 2015 1 comment

It has been an interesting week for me.  I managed a 10 minute CW QSO with G1SCS on 40m, a mode that I am steadily improving at as I continue with my QSO365 challenge this year.  I have also started work on a kit that arrived from China with no instructions and just a schematic to work from.  This is going to be fun to work out.  Also this week I won a radio on a well known Internet auction site.  The radio is a Trio TS-780 dual band base multimode from 1983.  I do understand that the power is a bit low on 144MHz and on 430MHz it is 5kHz out.  Therefore this will become a project for me as when I was first licenced as M1DKN back in the 90’s, this was a dream radio that I could not have afforded (well over £1000 for a second hand one then).  I am just waiting on delivery now so I can make a start on it.

As to the kit it is for a 49er –  a 3.5Watt CW transceiver.  I have so far installed and tested the DC supply regulator – a 78L08 and associated capacitors plus the input / output sockets.  Next stage will be the RX once I work out what needs to go where.  I am enjoying doing it though and scratching my head at times.  I shall be happy when I am able to make my first QSO on it.

CDf0j2jXIAE0WIcThe 49er so far.

ts780The TS-780 dual band base transceiver

QRP 365 Update 17

April 26, 2015 1 comment

It’s Sunday April 26th 2015 and I have now completed week 17 of my QRP 365 Challenge.  For those who are new to this, this means that for the whole of the year, 2015, I shall use no more than 5W and just CW or Datamodes, no phone at all.  At least one QSO a day – hence 365.

So how did I do this week?

20/04/15: UX0KR, 5W, PSK31 on 14.07015MHz, a distance of 1149mi (1854km) / 229.8mi (370.8km) per Watt.

20/04/15: ES3BR, 5W, PSK31 on 14.07015mhZ, a distance of 1056mi (1704km) / 211.2mi (340.8km) per Watt.

21/04/15: UR3CFC, 5W, PSK31 on 14.07015MHz, a distance of 1362mi (2196km) / 272.4mi (439.2km) per Watt.

21/04/15: R6LCG, 5W, JT65 on 14.076MHz, a distance of 1851mi (2985km) / 370.2mi (597km) per Watt.

21/04/15: LY2BOS, 5W, JT65 on 14.076MHz, a distance of 1006mi (1622km) / 201.2mi (324.4km) per Watt.

22/04/15: YO9BMN, 5W, JT65 on 21.076MHz, a distance of 1229mi (1982km) / 245.8mi (396.4km) per Watt.

22/04/15: LZ1UBO, 5W, JT65 on 21.076MHz, a distance of 1363mi (2199km) / 272.6mi (439.8km) per Watt.

23/04/15: OH8JGG, 5W, PSK63 on 14.07015MHz, a distance of 1167mi (1883km) / 233.4mi (376.6km) per Watt.

23/04/15: UT0IO, 5W, PSK63 on 21.07015MHz, a distance of 1698mi (2739km) / 339.6mi (547.8km) per Watt.

23/04/15: RD3FC, 5W, PSK63 on 21.07015MHz, a distance of 1581mi (2550km) / 316.2mi (510km) per Watt.

24/04/15: UA9LO/8, 5W, PSK125 on 21.07015MHz, a distance of 2507mi (4043km) / 501.4mi (808.6km) per Watt.

25/04/15: G1SCS, 5W, CW on 7.033MHz, a distance of 22mi (36km) / 4.4mi (7.2km) per Watt.

26/04/15: SV7NIN, 5W, PSK31 on 21.07015MHz, a distance of 1409mi (2273km) / 281.8mi (454.6km) per Watt.

As can be seen the best DX this week was UA9LO/8 with a cracking 2507miles (4043km) worked. Full credit has to be given to G1SCS for holding a 10 minute CW QSO with me in continuously worsening conditions with QSB and QRM increasing steadily.  I have also, this week, shipped the first batch of paper QSL cards via the bureau to stations worked so far, so please be patient, I know how long the bureau can take to get the cards to you but it is the best process.  Of course every station would have already received an e-qsl card from eqsl.cc as these are sent automatically by my logging program.

I am still continuing to call CQ using CW for the first 1/2 hour of my daily session and still not getting replies most of the time .  If we do wish to keep this mode alive it really does need using.  People may consider it difficult and out of date or unnecessary but it is all part of the history of what is a fascinating hobby and means of communication.  It is also a much cleaner signal than many, taking up just a few hundred hertz as opposed to kilohertz and is much less likely to cause TVI or EMC.  Give it a try, you may be surprised at just how easy it is.  It is also much easier to build a CW transmitter and receiver than it is to build one for phone so if you fancy a go at homebrewing some kit, this is probably the first thing to look at – a crystal oscillator, a buffer, an amp and a key to turn it on or off (not forgetting harmonic filters after the final stage so as not to annoy other users).

Talking of home brew kits, I have started work on a kit that arrived from China earlier this week.  It came with no instructions and a parts list written in Chinese (probably Mandarin).  When completed this will give me 3.5W on 7.023MHz CW.  It is certainly going to take a little longer as I am having to work things out myself but am using my experience of building kits from http://www.kanga-products.co.uk to help.  progress to date can be seen in the picture below. So far, the DC input regulator (12V supply to 8V throughput via a 78L08 and associated circuitry.  Next job will be the RX stages and crystal ladder filter.

CDf0j2jXIAE0WIc

Until next update..

Next update will be on Sunday 3rd May 2015.

QRP 365 Update 16

It’s Sunday April 19th 2015 and I have now completed week 16 of my QRP 365 Challenge.  For those who are new to this, this means that for the whole of the year, 2015, I shall use no more than 5W and just CW or Datamodes, no phone at all.  At least one QSO a day – hence 365.

So how did I do this week?

13/04/15: R9XAC, 5W, PSK63 on 14.07015MHz, a distance of 2507mi (4043km) / 501.4mi (808.6kmkm) per Watt.

14/04/15: ES3BR, 5W, PSK31 on 14.07015MHz, a distance of 1071mi (1715km) / 214.2mi (343km) per Watt.

15/04/15: RA3TAC, 5W, JT65 on 14.076MHz, a distance of 1768mi (2852km) / 353.6mi (570.4km) per Watt.

16/04/15: UR5LOS, 5W, JT65 on 14.076MHz, a distance of 1454mi (2345km) / 290.8mi (469km) per Watt.

17/04/15: UR4UHE, 5W, JT65 on 14.076MHz, a distance of 1319mi (2127km) / 263.8mi (425.4km) per Watt.

18/04/15: LY2BOS, 5W, JT65 on 14.076MHz, a distance of 1006mi (1622km) / 201.2mi (324.4km) per Watt.

19/04/15: IK0PAV, 5W, PSK31 on 14.07015MHz, a distance of 953mi (1537km) / 190.6mi (307.4km) per Watt.

As can be seen the best DX this week was R9XAC with a cracking 2507miles (4043km) worked. Not so many QSOs this week though as I have been awfully busy at work and finding the time to get on the radio has proved to be quite a challenge.  I have also, this week, taken delivery of my DxCoffee QSL cards printed by TopQSL.com.  One of these will be sent out to every station worked via the bureau, so please be patient, I know how long the bureau can take to get the cards to you but it is the best process.  Of course every station would have already received an e-qsl card from eqsl.cc as these are sent automatically by my logging program.

QSL Cards

I am still continuing to call CQ using CW for the first 1/2 hour of my daily session and still not getting replies most of the time .  If we do wish to keep this mode alive it really does need using.  People may consider it difficult and out of date or unnecessary but it is all part of the history of what is a fascinating hobby and means of communication.  It is also a much cleaner signal than many, taking up just a few hundred hertz as opposed to kilohertz and is much less likely to cause TVI or EMC.  Give it a try, you may be surprised at just how easy it is.  It is also much easier to build a CW transmitter and receiver than it is to build one for phone so if you fancy a go at homebrewing some kit, this is probably the first thing to look at – a crystal oscillator, a buffer, an amp and a key to turn it on or off (not forgetting harmonic filters after the final stage so as not to annoy other users).

Until next update..

Next update will be on Sunday 26th April 2015.

QRP 365 Update 15

It’s Sunday April 12th 2015 and I have now completed week 15 of my QRP 365 Challenge.  For those who are new to this, this means that for the whole of the year, 2015, I shall use no more than 5W and just CW or Datamodes, no phone at all.  At least one QSO a day – hence 365.

So how did I do this week?

06/04/15: IK1BES, 5W, JT65 on 14.076MHz, a distance of 953mi (1537km) / 190.6mi (307.4km) per Watt.

06/04/15: SG3TGQ, 5W, JT65 on 14.076MHz, a distance of 904mi (1458km) / 180.8mi (391.6km) per Watt.

06/04/15: UA3LHA, 5W, JT65 on 14.076MHz, a distance of 1851mi (2985km) / 370.2mi (597km) per Watt.

07/04/15: IZ0UIJ, 5W, PSK31 on 14.07015MHz, a distance of 957mi (1544km) / 191.4mi (308.8km) per Watt.

07/04/15: C35MF, 5W, PSK31 on 14.07015MHz, a distance of 717mi (1156km) / 143.4mi (231.2km) per Watt.

07/04/15: R120RX, 5W, PSK31 on 21.07015MHz, a distance of 1851mi (2985km) / 370.2 (597km) per Watt.

07/04/15: SP2CBS, 5W, JT65 on 14.076MHz, a distance of 797mi (1276km) / 159.4mi (255.2km) per Watt.

07/04/15: IW1APE, 5W, JT65 on 14.076MHz, a distance of 656mi (1051km) / 131.2mi (210.2km) per Watt.

07/04/15: UR7GO, 5W, JT65 on 21.076MHz, a distance of 1343mi (2150km) / 268.6mi (430km) per Watt.

07/04/15: UW1HM, 5W, JT65 on 21.076MHz, a distance of 1343mi (2150km) / 268.6mi) 430km) per Watt.

08/14/15: 9A4FS, 5W, PSK31 on 14.07015MHz, a distance of 896mi (1434km) / 179.2mi (286.8km) per Watt.

09/04/15: M0OBL, 5W, JT65 on 14.076MHz, a distance of 3mi (4.83km) / 0.6mi (0.97km) per Watt.

09/04/15: IZ2ODN, 5W, JT65 on 14.076MHz, a distance of 953mi (1537km) / 190.6mi (307.4km) per Watt.

10/04/15: UX0KR, 5W, PSK31 on 14.07015MHz, a distance of 1149mi (1854km) / 229.8mi (370.8km) per Watt.

11/04/15: SQ4OJL, 5W, JT65 on 14.076MHz, a distance of 843mi (1360km) / 168.6mi (272km) per Watt.

11/04/15: DC7TO/P, 5W, PSK31 on 14.07015MHz, a distance of 585mi (944km) / 117mi (188.8km) per Watt.

12/04/15: UA1CDI, 5W, PSK31 on 14.07015MHz, a distance of 1258mi (2029km) / 251.6mi (405.8km) per Watt.

12/04/15: OH6FSO, 5W, JT65 on 14.076MHz, a distance of 1069mi (1742km) / 213.8mi (348.4km) per Watt.

12/04/15: LY2BOS, 5W, JT65 on 14.076MHz, a distance of 1006mi (1622km) / 201.2mi (324.4km) per Watt.

As can be seen the best DX this week was shared between UA3LHA and R120RX both  with a cracking 1851miles (2985km) worked. It was also interesting to work M0OBL again on a different band this time, just 3 miles down the road on 20m (probably on a ground wave) showing that local contacts are possible on the higher HF bands.

I am still continuing to call CQ using CW for the first 1/2 hour of my daily session and still not getting replies most of the time .  If we do wish to keep this mode alive it really does need using.  People may consider it difficult and out of date or unnecessary but it is all part of the history of what is a fascinating hobby and means of communication.  It is also a much cleaner signal than many, taking up just a few hundred hertz as opposed to kilohertz and is much less likely to cause TVI or EMC.  Give it a try, you may be surprised at just how easy it is.  It is also much easier to build a CW transmitter and receiver than it is to build one for phone so if you fancy a go at homebrewing some kit, this is probably the first thing to look at – a crystal oscillator, a buffer, an amp and a key to turn it on or off (not forgetting harmonic filters after the final stage so as not to annoy other users).

Until next update..

Next update will be on Sunday 19th April 2015.

A8FFS-1CcAAV7U2

 

QRP 365 Update 14

It’s Sunday April 5th 2015, Easter Sunday, and I have now completed week 14 of my QRP 365 Challenge.  For those who are new to this, this means that for the whole of the year, 2015, I shall use no more than 5W and just CW or Datamodes, no phone at all.  At least one QSO a day – hence 365.

So how did I do this week?

30/03/15: HA2NL, 5W, PSK31 on 14.07015MHz, a distance of 952mi (1535km) / 190.4mi (307km) per Watt.

31/03/15: IK2WAS, 5W, PSK31 on 14.07015MHz, a distance of 647mi (1044km) / 129.4mi (208.8km) per Watt.

01/04/15: OE6IWG, 5W, JT65 on 14.076MHz, a distance of 771mi (1244km) / 154.2mi (248.8km) per Watt.

01/04/15: RW0BT, 5W, JT65 on 14.076MHz, a distance of 2497mi (4027km) / 499.4mi (805.4km) per Watt.

02/04/15: UT1WR, 5W, PSK31 on 14.07015MHz, a distance of 1079mi (1740km) / 215.8mi (348km) per Watt.

03/04/15: M0OBL, 5W, JT65 on 21.076MHz, a distance of 22mi (36km) / 4.4mi (7.2km) per Watt.

04/04/15: IZ6GVC, 5W, JT65 on 14.076MHz, a distance of 953mi (1537km) / 190.6mi (307.4km) per Watt.

05/05/15: YO9BLY, 5W, PSK31 on 14.07015MHz, a distance of 1293mi (2086km) / 258.6mi (417.2km) per Watt.

05/04/15: AM590RKE, 5W, PSK63 on 14.07015MHz, a distance of 1000mi (1613km) / 200mi (322.6km) per Watt.

As can be seen the best DX this week was RW0BT with a cracking 2497 miles (4027km) worked. It was also interesting to work M0OBL, just 22 miles down the road on 15m showing that local contacts are possible on the higher HF bands.  Notably there was much more CW activity on all bands this morning for the SP Contest but again, 30 -40 wpm is outside of my realm and I do not believe contest results should be included as part of this challenge.  However, if so many are able to use CW during contests, why are they not around at other times for a standard QSO and rag chew?

I am still continuing to call CQ using CW for the first 1/2 hour of my daily session and still not getting replies most of the time .  If we do wish to keep this mode alive it really does need using.  People may consider it difficult and out of date or unnecessary but it is all part of the history of what is a fascinating hobby and means of communication.  It is also a much cleaner signal than many, taking up just a few hundred hertz as opposed to kilohertz and is much less likely to cause TVI or EMC.  Give it a try, you may be surprised at just how easy it is.  It is also much easier to build a CW transmitter and receiver than it is to build one for phone so if you fancy a go at homebrewing some kit, this is probably the first thing to look at – a crystal oscillator, a buffer, an amp and a key to turn it on or off (not forgetting harmonic filters after the final stage so as not to annoy other users).

Until next update..

Next update will be on Sunday 12th April 2015.

A761JdACAAEQTZt