4 summits activation

Hi all,

Another weekend, another time to get out and have a look at some SOTA summits.

The plan

The plan for this trip was to activate four summits that I had not activated before, VK3/VN-006, 007, 008 and 010. VK3/VN-006 Keppel Ridge is a summit in the shadow of Lake Mountain. The other three are fairly close together a bit further to the east. I started off heading down the Eildon Warbuton Rd, which starts off quite wide, and made my way along to a road to go across to Mt Duffy VK3/VN-007. I found out that Gum Top Rd was closed due to a planned prescribed burn, along with Rough Hill Rd. Even Reefton Logging Rd was closed, so I could not access Mt Duffy, with the two other SOTA summits behind it. Well, I’m out here, I might as well activate something.

Keppel Ridge VK3/VN-006

This was my last planned summit of the day, but it ended up being the first. I headed up Sandstone Rd up to point (ed) 057485. This is a little down from saddle which has a lot of logging regrowth. We would like to avoid that horrible stuff. The forest a little lower down is quite open and gives reasonable access to the summit. Up on top, I ended up activating only a little late from my planned activation of VN-010, and there was plenty of chasers waiting on 40m.

Federation Ridge VK3/VN-003

Next up, to make for a complete day, I wanted to still get 4 summits in. I headed for Lake Mountain, after checking that I had not activated this summit this year. With many summits in VK3, I would rather get fresh activator points for each activation than not. As this summit can be worked on 2m I decided to go for that. Also, last time I was here, I could not use the 2m colinear. I was eager to have a look at the difference. Last time, I could only work Peter VK3PF on SSB, and signals were 51 both ways, good readability, but weak on a 1/4 wave. This time it was 58 and 53, so much better. All the other stations worked were different from last time. It was lightly raining, so I aimed to keep the activation short to not get too wet and to keep the chance of getting four summits in.

Sugerloaf Peak VK3/VN-011

Next up, a good sporting summit with a bit of a rock scramble. It had not rained here yet, so the rocks were dry on the way up. I was tempted to join the dog piles on 40m, but again this was a summit where V1 of the colinear had failed. I was keen to try it here again. This time it failed again! I checked things out and found it was my FM series match stub. I had to use the colinear unmatched, but VK3FABA reported me 58 on the 1/4 wave reported me 60 over on the colinear. Perhaps not really 60 over, but it’s more about 25dB to 30dB up.

Unmatched, the colinear has an SWR of around 2.5, which is not great but it still puts me in business. I’ll need a soldering iron to repair the stub.

I could here Peter VK3PF call on SSB, but he could only dimly hear the CW I sent back. I think a matched colinear could get to Churchill from here, on 5W QRP.

Mt St Leonard VK3/VC-006

Final activation of the day is an old favourite. I went for a quick activation, huddled underneath the public lookout platform for a little bit of shelter. The metal around improved the unmatched colinear to an SWR of around 1.7

It was nice to be able to work Peter VK3PF from here 2m into Churchill. Everyone else was LOS, so plenty of 59 signal reports.

In all, I missed out on the 4 new uniques, instead only adding one. Walked away with 26 SOTA activation points rather than 24. I think my priority order for SOTA is:
1/ New activation uniques
2/ Activation points
3/ S2S points
4/ Chaser points (nice to get if they are there)

Also, I like a challenge, and 2m provides more of that challenge (so long as it is a realistic challenge). 40m has plenty of pileups these days to keep SOTA quite active there, but where 2m is possible, I’ll think I’ll focus on that.

Maybe, I should try 40m CW only as a bit of a challenge and join VK3BYD!

One final note: The internal batteries on my FT-817 are not giving as much operating time as they used to. I reckon its down to about 50% of new. They have had a fair amount of use, but this is not really a fantastic service life. Looks like I’ll be going to an alternative soon. I think I will give the HobbyKing NiMH AA cells a good spin as they look good, otherwise a LiPO will be going in there.

73 Wayne VK3WAM

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Pyrenees Trip

Hi all,

After my recent trip around VK1, I thought it time for something a little more conventional and a bit easier. I was heading up to Ballarat to spend time with family, but there is always some time for a little SOTA on the side. I thought I was good for two half days, but I was able to upgrade this to a day and half.

VK3/VC-032

First summit up was an unnamed summit between Ballan and Daylesford. There are a number of named summits in this area, but the highest ground is a little nondescript. Nonetheless, I had not activated this summit before, so it was one to add to the collection.

Access is quite easy, as many tracks are quite a good 2wd gravel standard. The high area consists of two hill tips with a shallow saddle between them. This saddle is less than 25m vertical down from the summit, so both hill tops (and the saddle as well) are in the activation zone, making it quite large. I picked an area near the top, set up the squid pole for 40m and got down to business.

Squid pole and end fed for 40m pictured when operating at VK3/VC-032

Operating at VK3/VC-032

VK3/VC-021

With this summit in the bag, it was time to check out Smeaton Hill. This is a private land summit. The owner lives in a house on the northern side of the hill. I dropped in and knocked on the door, but no one was home. End of this activation.

Mt Warrenheip VK3/VC-019

I still had enough time to swap in an alternative location. I had activated this summit the previous year, but it was still good for fresh activation points. A quick trip up, parking the car about 2/3rds of the way up. A simpler activation here than last year, just sticking up the end-fed, but no 20m CW action into Europe. Sometimes I miss the vertical, so I’ll need to get it out at some stage. It does not lend itself to doing many summits in one day, due to the setup and takedown time.

Mt Warrenheip has recently been burnt by fire, but the fire looks fairly mild. It got into the canopy of the trees, but the big trees should quickly recover.

With the activation done, my half day was up.

Blue Mountain VK3/VS-015

I then had a whole day to look at doing SOTA activations, so I thought I would try for 5 in one day. First up, Blue Mountain. This summit can be accessed from Glenlofty Warrenmang Rd, which heads through north-east to south-west through these hills. This is a good 2wd track, and about 997966, there is a 4wd track heading off to the west-north-west. This is passable in a 2wd with care. I was able to head through to 973977, where I left the car. This shaved off about 3km and was a nice little bonus. It was less than 1km from there to the summit. Here’s the operating shack:

Rig, cables and the feedpoint of the end-fed at VK3/VS-015

Operating at VK3/VS-015

And the squid pole:

End-fed mounted on a squid pole in forest at VK3/VS-015

Antenna at VK3/VS-015

One thing to note about these forests is how open they are. A stark contrast to the heavy bush bashing up in VK1 the previous weekend.

VK3/VS-018 Point 756/Pyrenees

Next up was a summit on the other side of Glenlofty Warrenmang Rd. This time it was a nice 2wd track heading up the hill, until I found a large tree across the road. Should I drive right out and come in the other side? After about 5 minutes, I thought I have to walk it – about 5km to the summit. I walked/jogged sections along this, trying to get to the summit before the UTC midnight changeover, for the eager chasers wanting to work the summit twice. I ended up on the air less than 2 minutes to go, where I worked 9 stations in the remaining time. I stayed for about 20 minutes after the UTC midnight changeover and worked most of them again.

One of the challenges of this trip was stretching the battery life over. I was using the leftovers that were unused from the VK1 trip – one 2.2Ah LiPo, plus the stock internal battery of the FT-817. This had to do all the four summits up to now, plus the 3 remaining summits. As of now, the 2.2Ah LiPO had done 4 summits, and was getting a little low, but still had a little left. The internal battery was still mostly fresh.

It’s nice to also clock up a few summits to summits (s2s) on this activation. These contacts always add a little buzz, and I’m even working my way up the s2s list here, although I really only target the activators points and especially uniques lists.

Time for another 5km march back to the car with the fallen tree. When I got there, there was another guy stuck there contemplating ringing up the local authority to get the road cleared.

VK3/VS-009 Ben Nevis

It was time to grab a quick bite and head up to Ben Nevis. This summit has a 2wd track that goes all the way to the top. I try to park out of the activation zone and walk in, rather than drive to the top and walk down and then up, where possible. There are two towers, plus a weather station up top. I headed over to a rocky area beyond that, which was a little higher.

Here’s some of the views:

Langi Ghiran and distant Grampains from Ben Nevis

Langi Ghiran and distant Grampains from Ben Nevis

Open plains NW from Ben Nevis

Looking NW from Ben Nevis

On commencing operations here, I got a first up distress call from VK3UP, who had come across a fallen motorcyclist near Mt Disappointment. It was also clear that many of the waiting SOTA chasers could not hear him. Andrew VK2UH could and he kindly took over handling the situation. Given that I was already stretching out the batteries, it was better for a home station to handle this. Andrew arranged the calling of the ambulance to help, and then had to relay comms for emergency services as they were unable to communicate themselves from the location of the accident.

I headed up 5kHz and activated the summit from there. It was a smaller chasing crowd – I presume some of the usuals were listening in to the emergency situation 5kHz down on the calling frequency. There was no problems experienced from the commercial gear up on the summit.

Here’s a look at the main tower at Ben Nevis:

Main commercial tower and fire lookout at Ben Nevis

Main commercial tower and fire lookout at Ben Nevis

Mt Cole VK3/VS-008

Mt Cole is a tricky little summit. It does not have 2wd road access, so I tried going down a rough track starting at 012668, so I could approach the summit without having to do too much climbing. This track is really too rough for a 2wd. It would have been better to park at 018667 and walk from there. Frees Point Rd could be used, but I headed up off track, basically going up the spur.

Upon reaching the top, I put up the end fed as usual, but then noticed that the UHF connector had come apart – basically a break in the centre conductor near the crimp joint through repeated stresses over time. I put the other end of the coax into the end-fed match box for a secure connection and got out the pocket knife to do something at the radio end, and this is what I came up with:

Coax stripped back going directly into the UHF connector on a FT-817

Jury rig job to get on the air 40m without a connector

It was a bit fragile, especially if I moved, I might have moved sticks, grasses or whatever that would affect the connection. I had to break here and there, but I got the activation done.

Time was pressing on, but the power side was still holding up. I had the chance for one last activation, after returning to the car and finding out I had not trashed it on that rough 4wd track.

Mt Lonarch VK3/VS-013

The final activation of the day was a nice easy one. The road goes all the way, but it actually goes past and loops back. I parked about 40m vertical down from the top and “bush-bashed” over to the summit. It was not real bush-bashing because the forest is quite open with a grassy forest floor. Again, I had to rely on the jury-rigged cable to bring the activation home, but it worked.

I also walked out with around about 45 minutes of operating time still up my sleeve. The 2.2Ah LiPO could have still been used for another 1/4 of an hour and the internal battery was only about 2/3rds used. So 7 summits out of one 2.2Ah battery plus a bit of internal battery top up is not bad going! Total operating time would have been over 3 hours with still 3/4 of an hour in the bag.

It is interesting these days to work 40m. Certainly there are some nice decent pile-ups happening, but operators are waiting in turn. Hopefully we keep things going well in conducting the dog-piles and the chasers are patient with new activators who perhaps might not be used to having 5 stations answer their CQ all at once. It is still a far cry from the days early last year where one could activate a summit for SOTA, and call CQ for an hour and have no one come back. Things are better these days.

Nice to get 7 summits, with 6 new ones in. I’m now only three new summits away from 100 unique summits.

73, regards, Wayne VK3WAM

Designing a 20/40 band CW rig – Part 1

Hi all,

I have been spending some time working on the design of a ultra portable CW rig. I’ve been spending time looking at various kit designs from Steve KD1JV, Ramsey Kits, You Kits, the Elecraft KX1 and others. Some rigs are quite simple, others have a more sophisticated approach.

Goals

In setting down to design a rig, I was wanting something that would work well in a SOTA activation context. I would want the rig to do the following:

  • I did not want to be limited to a narrow band of frequencies around a crystal, but wanted the whole band to be available.
  • The power output needed to be around 5W – full QRP. 500mW CW can be tough going in VK. One attraction with SOTA activations is working the DX chasers, so 5W is nice, while keeping the QRP endorsement intact.
  • I’d like to keep open the option of some digital modes, even if the rig would not do these directly itself.
  • The rig would need RIT.
  • If possible, to switch bands without needing to use external switches.
  • Deliver near 5W from a 12V source, safe for 12.6V – a three series LiPo cell, usable down to 9V.
  • Do all of this in a kit that would cost less than US$200, good, $150 better, $100 best – but no promises!

Overall rig design

The rig could basically be broken down into a number of sub-sections.

  1. Power – a cut-off for low input voltage, and regulators for 5V and 3.3V
  2. Audio frequency – RX audio and sidetone
  3. TX – SSB rigs mix up, but this being a CW rig, I only need to switch an oscillator output and amplify up to 5W. I also need to impedance match for 50ohms at the RF connector
  4. Oscillator – Given my tune the whole band requirement – I’m going to need a PLL and VCO or equivalent circuit, such as a DDS.
  5. RX – Taking the RF connector, I need to either use a relay to switch away the TX, or a transistor switch. I then feed a mixer to an intermediate frequency for filtering, and then can feed a second mixer to audio frequency
  6. Control – Need to use an embedded controller – I am familiar with the PIC line, so I’ll use something there. This will need to set dividers for the PLL or DDS, take button input from the user for tuning, band selection, RIT, provide a keyer facility (I won’t be using a straight key) – with the ability to configure at least the wpm send rate

I’ll go through these in greater detail over a number of posts. I have been influenced by some of Steve KD1JV’s ideas, but also want to do some of my own things. I have already mentioned that I want internal band selection. I also want a volume control, with the rig able to drive at least a 16 ohm speaker, along with low impedance head/ear phones – like the ones supplied with mobile/cell phones. I also want it to be capable of driving 200 ohm headphones.

Above, I floated ideas of how to switch TX/RX. A relay could be used, but if full break-in is going to be supported, relays are a pain. Relays are good for things like band switching – ’cause you don’t switch band 100 times a minute, but to keep the power down, they will need to be latching.

At time of writing this post, I have most of the sub-section circuits designed and thrashed through simulations and a bit of bread boarding. I’ll hopefully put up some posts over the next few days or so looking at TX, the audio section and some of the RX.

This design is going to be largely SMT, but to keep things sane, I’ll use 0805 or larger size components. I could make it thru-hole, but the physical size would be much larger, and it would be significantly more expensive.

73 de Wayne VK3WAM

Continued in Designing a 20/40 band CW rig – Part 2

Upgrading a camping lantern

Hi all,

My family goes car based camping a few times a year. I also go pack carry camping as well, but that requires a different set of gear. A number of years ago I purchased a 7W fluorescent camping lantern. It has worked well, but now the battery is cooked. Here’s a look at the box of the product.

Wild Country 7W camping lantern

Designed to fail

The cheaper – and not so cheap – lanterns can often have a poor design that can lead to early failure because they do not treat the internal battery appropriately. These units are often supplied with an internal sealed lead acid battery (SLA). My one had a 4Ah 6V battery. This can power the lamp for about 3 1/2 hours. One problem is that SLA batteries should not be cycled more than 50%. They also should be stored fully charged. The 50% cycle means that this lantern should have only been used for 1 3/4 hours on a full charge, and then it needs recharging. No mention of that in the small manual that came with the lantern.

The second problem is that the charging circuit built into the device does not charge the Pb battery in a way that is according to spec. The charging voltage is too high. It’s going to cook the battery a little bit on each charge.

So now I have a lantern that does not work. Should I just throw it away?

Solution

The rest of the lantern seemed ok, it just didn’t have a working battery. I could have just bought a new battery from the supplier, but they charge more than the cost of a new lantern. So, I thought I would replace the battery with something that was more suitable.

Firstly, I have been using LiPo packs in Amateur Radio applications – powering a low and a moderate power radio. A 3S – 3 cells in series pack has a voltage of 10 to 12.6V. Too high for this lantern directly, but it could be converted to 6V. I found some LiPos at Hobbyking that would do the trick.

Hobbyking 2200mAh 3S1P Turnigy

Three of these fit into the battery area of the lantern quite snugly. I cut the main cable to a short run and used JST-XH connectors, which are shown in the picture above, as these connectors are the same on my other LiPo’s – makes it easy to charge on the chargers that I already have.

Having three of these inside, with 6VDC regulation, gives me capacity over 3 times the old battery, but I can use nearly the whole cycle, so it is really 6 times the capacity.

I grabbed a DC converter off Ebay that outputs 6V up to 3A. The lamp draws about 1.2A, so that is easy going for this converter.

I would not be using the existing charging circuit. It was no good for the Pb battery, and it certainly would be no good for these LiPo packs. I could make use of the LED in the lantern that indicates when the lantern is charging. Instead, I would use this LED to indicate that the voltage in the LiPos was good. The 6V converter would work with an input voltage of 7V, which would mean the LiPo packs driven down to an average of 2.3V per cell – far too low. Instead, I would use this LED to indicate when the packs were getting flat, at around 11V or just a little under. The LED would be on when the battery was ok, and go off when not.

I needed a simple circuit to drive the LED. From the LiPo voltage source, I fed a 470ohm resistor and then three Zeners. I selected three, because the breakdown voltage of around 11V was what I needed, and I had these on hand. Three of these zener diodes, each with a breakdown voltage of 3.6V, in series gave me what I needed. The current on the zeners would be about 3mA – set by selecting the 470 ohm resistor. Connected between the Zeners and the resistor is the base of a 2n4401 transistor, with the LiPo voltage on it’s collector. From the emitter of the transistor, I had a 1K resistor. This would have typically about 9V across it, meaning a current of about 9mA. This was in series with the LED, which has it’s own 2V drop. So from the LiPo voltage, the transistor would have a drop of around 2V when the LiPo pack was fully charged, falling to zero when flat, plus just under 9V for the resistor and 2V for the LED.

This circuit was put onto some veriboard and put into the lantern’s battery compartment. It is shown below and the DC converter is immediately beside it. Below is the factory built charging circuit that is now unused.

Unfortunately, I mixed up one of the JST-XH connectors on one of the LiPo packs, with the plastic housing having wrong polarity. I made one of the associated connectors to match it, and marked them both with tape so I don’t use it for the other packs. I’ll just have to live with it.

After all of that, it was time to turn it on. Works well – very pleased with the outcome. Now, I can safely use the lantern for about 11 to 12 hours between charges, rather than under 2 hours. This has turned into an upgrade rather than a repair of the lantern.

Regards,
Wayne Merry

FT-817 Internal battery ideas

These days, FT-817ND units are supplied with the Yaesu FNB-85 battery pack. This pack consists of eight NiMH AA cells in a shrink wrapped package. The rated capacity of the pack is 1400mAh. NiMH cells have a nominal voltage of 1.2V, so 8 times this is 9.6V.

The capacity of this pack gives me about an 1 1/2 to 1 3/4 hours during a SOTA activation. SOTA activations at the moment can involve a lot of CQing, so my rough estimation is that I would be looking at a TX duty time of at least 30%. I also have a BHI filter installed, so my 817 is heavier on current draw on receive – about 417mA with the volume down, and 430mA typical on receive. Obviously more on TX. This leads me to believe that at the moment, I am getting capacity “in the ball pack” of the rated capacity.

Quite a number of my trips involve multiple activations on a single day or trip, and the internal battery is not enough to keep going the whole time. At the moment, I supplement the operating time I get from the internal battery by using either LiPo packs or three LiIon 18650 cells in series in some PVC pipe, and then plugged in via the external DC jack. This is meeting my needs for the moment.

There is no doubt that by using 3 cell Lithum technologies, there is plenty of options for external power. What about internal – when the FNB-85 dies sometime in the future, I will want to replace it, but I want something better. Given that it is working well at the moment, it would be a little indulgent of me to replace it now, so I won’t – but it is nice to have a plan. It is also nice to have more capacity than 1400mAh. Something north of 2000mAh, perhaps even 2500mAh should be achievable.

A LiPo pack in the internal battery slot

Glenn, VK3YY experimented with putting a Turnigy LiPo inside the FT-817. See his picture below:

Turnigy LiPo 2500mAh battery

This battery can be found at HobbyKing at:

http://www.hobbyking.com/hobbyking/store/__23814__Turnigy_nano_tech_2500mAh_3S1P_5_10C_Transmitter_Lipo_Pack_.html

It has a lower C rating than many LiPos as it is optimised for RC transmitters, rather than the boat, plane, helicopter at the other end that could be drawing 100A plus. The FT817 is going to only hit it with 2A, which is only 0.8C – a walk in the park given its 5C discharge rating. The voltage of the pack would be 12.6V fully charged and 11V or so when discharged – so the voltages will be perfectly fine for the 817. Some care is needed as the battery will provide some additional operating time down to 9V, but this is not recommended. The operator needs to pay attention to the voltage display on the 817 screen. The 817 cutoff is 7.5V which would drive the LiPo pack too low – this is 2.5V per cell if it was perfectly balanced. If even a little unbalanced, one cell would be even lower, which is not good.

The LiPo is is a good solution, but it is a higher maintenance solution given the cut-off issue above. The FT-817 is also not designed to charge LiPo packs, so the LiPo needs to be taken out to be charged. It really needs a proper LiPo balance charger to keep the cells in line with each other. Care would need needed if this battery was installed fully charged and an external DC power supply be attached, as unless the green battery cable is connected to a meaningful voltage, the FT-817 will trickle charge 10mA into the battery. This is bad for a fully charged LiPo pack!

NiMH solution

The 817 is supplied these days with the FBA-28 battery holder. This is designed for use with Alkaline cells. These cells are not going to handle a 2A current draw very well, so I can’t imagine that there are many in the world who are using this holder in this way. The holder is pictured below:

FBA-28 battery holder

I have put in a number of Energizer 2450mAh NiMH battery cells into the holder. Eight are needed to complete the pack. The pack is a little difficult to get into the 817, but the trick is to put the holder in first empty, and then put the batteries in.

Yaesu do not recommend using rechargables in this pack. The main reason for this is suspected to be the risk of a short. The Cathode of a rechargable AA NiMH is the outer shell. Aside from the last cell in the pack, this will have a voltage difference to the case, and some of the cells can rest against the case. The only protection against disaster is the outer label on the cells, and this can be scuffed away. The picture shows that there is a plastic tab that will cover about 2/3rds of the lower 4 cells, but some electrical tape put over the exposed cells will also aid in providing the necessary protection. I would not think it needs to be comprehensive coverage, but two strips over the top 4 cells, top and bottom, and one strip over the 4 bottom cells at the exposed tops should be enough. (Of course half the cells are facing the other way so their top will be the other cell’s bottom, etc).

One final modification is the green cable. This is connected between cell 4 and 5 in the pack. If this cable remains connected, the FT-817 will not charge the pack. This cable needs to be cut and secured, and then everything will be ready to go.

Appropriate NiMH cells

My picture above shows Energizer NiMH cells. These are rebranded Sanyos. They work well in many applications, but unfortunately, not this one. Even though fully charged, the voltage drop when the 817 hits them with near 2A is too much, and so the effective life of the pack is much lower than the 1400mAh Yeasu pack. The labeled 2450mAh capacity sounds real nice, but the real world experience would suggest much different. I have tried them in non-radio applications with current draws of around 500mA, and they work ok there.

I found that HobbyKing sell NiMH cells, including some low discharge 2400mAh cells. This is a great capacity for a low discharge cell. I have also read that some have tested these cells at 3A and they work well. I am getting some of these cells to give them a test, but if they can handle 3A, they would be a great cell to use in the Yeasu battery holder. The 2400mAh capacity nearly matches the 2500mAh LiPo pack. Both solutions should give nearly 3 hours of heavy SOTA activation time, but the NiMH solution can use the internal Yaesu charger (2x 6 hour charges back to back), and there are no concerns about damaging the pack if taken to 8V or so.

Regards,
Wayne VK3WAM