QRP SSB on 40 metres: portable from the beach

What happens when you slice off the unwanted sideband but keep the output power the same? You get better signal reports and longer distance contacts.

Under test today is a 7 MHz QRP SSB transceiver. It was actually built several years ago but I wasn't really happy with its performance until recent mods.

It's previously worked DX from home when teamed up with an amplifier, but today's beach outing was the first time it was used portable.

The contacts recorded here were made over a two hour span between roughly 6 and 8pm (local time). The antenna used was a 1/2 wavelength end-fed with a short counterpoise.

Most contacts were locals, who gave good reports. However the day was really made great by working ZL, a couple of thousand kilometres away.

The rig itself is very similar to VK3XU's TCF series of transceivers. These are described in the book 'Radio Projects for the Amateur' (Vol 1) and Amateur Radio magazine for May 1995 (TCF 40).

Category:

Howto & Style

Tags:

• amateur
• ham
• radio
• homebrew
• QRP
• SSB
• portable
• 40
• metres
• transceiver
• NE602

[combatwombat71]

Very nice radio Peter - well done. You must let me know where you manage to get those Vernier drives. Haven't seen them commercially for years... 73 - Rob VK2GOM

[vk3ye]

@combatwombat71 Hi Rob, don't know of any new, but they sometimes pop up on eBay.

[mstax]

Does a beach location help with lowering noise - such as the wall-of-noise one gets in a city or suburb? I would guess so, but havent made the trek as yet to find out? Lately the noise on 20 meters around here is S8 or higher...

[vk3ye]

@mstax Yes. Even being 100 metres from the nearest house (instead of having 20 or more homes within 100m) helps greatly.

[m0dad]

Great video Peter and very well documented. Its amazing what can be done with 2 watts. I have made it over the pond from the UK to USA a couple of times with my 2 watt 40m tcf rig and dipole antenna. It would be very interesting to see the inside of your rig. I wonder what mods you made as I also made several on mine. What construction style did you use?

I like the enclosure it looks a very tidy project. Keep up the great work. All the best from David (M0DAD)

[vk3ye]

@m0dad David, none of the mods made were due to the failing of the original design - all were due to laziness and cutting corners. For instance IIRC I only have a single tuned circuit on the Rx input. There are a few weak rx spurs so 2 is better, as per the original design. But in no case have they been strong enough to prevent a contact.

[emercito]

Ahahahaha man, it´s amazing. Nice device, nice contest and comments. Tell me about it´s antena Best 73 to you :)

[VK2BEN]

Great work, Peter!

I recommend QRP-philes check out your website. Quite inspirational and motivational for the budding - or the experienced - QRP builder/operator.

73 Ben VK2BEN

K

[VictoreCelia]

Very nice transiver. Super recption and looks great...

73 from Portugal

[vk3ye]

@raccoonnyc Build style is a mix - PC board with pads glued onto it for the stages using discrete components (eg VFO, driver, PA) and matrix board for most of the rest. The VFO is in a small box up the middle and the Tx and Rx are on boards either side. The PA and T/R switch is up against the rear panel. Box style is actually a pain - too chunky and lets sand in. YouTube doesn't allow URLs, but there's nearly a full circuit by searcing 'VK3XU TCF' and finding M1KTA's blog.

[raccoonnyc]

Hi Peter,

Like David, I would also like to see the inside and more construction details. Nice Job and thanks for the video.

Tom, ak2b