Other SOTA sites: SOTAwatch | SOTA Home | Database | Video | Photos | Shop | Mapping | FAQs | Facebook | Contact SOTA

Four Metres


#1

During a chat with Tom M1EYP he pointed out that while 2m CW was quiet, if I really want to enjoy the peace of the hills I should build a rig for 4m. That throw away remark led me to think that if I build a modular radio I can easily make it operate on any band that I care to try. Thus I have built a sythesiser:

I have fed this into a wideband power splitter and I now have an incredible 4mW on 4m. This will be used with a general purpose 25MHz IF strip and power amplifier to make a 20W 4m CW transceiver.

Now a question: do any SOTA chasers have 4m CW capabilities?

73

Richard
G3CWI


#2

Now a question: do any SOTA chasers have 4m CW capabilities?

Now two possible answers:

  1. If not, then recruit some new ones from whoever is out there doing 4m CW.

or

  1. They will have soon enough if you start doing regular 4m CW activations.

Tom M1EYP


#3

In reply to G3CWI:
Ready when you are…
Home-brew transceiver on 28Mhz, G4DDK Meon Transverter and if needed 4CX250B PA to 3ele beam…
73,Mike g0bpu


#4

In reply to G0BPU:

Great stuff Mike. Could be that rare event of an homebrew-homebrew contact - far rarer than an S2S contact!

73

Richard
G3CWI


#5

In reply to G3CWI:

Now a question: do any SOTA chasers have 4m CW capabilities?

Yes,

Mike G4BLH


#6

In reply to G4BLH:

yes also

David g6lkb


#7

In reply to G3CWI:
Yes :o),

TS-711 driving a Spectrum transvertor.

Graham G4FUJ


#8

In reply to G3CWI:

Now a question: do any SOTA chasers have 4m CW capabilities?

It’s not popular for SOTA, mostly I suspect because the FT-817 doesn’t do that band. Although there are an increasing number of Chinese built 4m Handies around, mostly FM only I suspect.

Which brings me to a question I’ve been meaning to ask Richard for some time. Is there detailed design information available for your home brew kit?

I’m sure several of us would be interested in building them if information was available. I’ve got a kit for an ATS-3B waiting to be built so I’m not interested in your PP3 design but I would be interested in a 4m design.

However I’m not a radio engineer, or an electronics one for that matter. But, I can follow instructions and use a soldering iron and I do have access to some test equipment (at work). I’ve built several simple things like the Fox Delta APRS tracker board without trouble and don’t expect to have too much trouble with the ATS-3B even though it has quite a high SMT count.

So, perhaps not an actual kit, but maybe a pcb and some docs to enable others to build the 4m rig?

Colin G8TMV


#9

In reply to G8TMV:

Which brings me to a question I’ve been meaning to ask Richard for
some time. Is there detailed design information available for your
home brew kit?

Colin

There is no detailed info - and there is unlikely ever to be any. I build gear for my enjoyment. It is not designed to be repeatable and uses random components from my extensive “junk box”. Rather like a painting, the designs evolve during construction and testing and in the end I have no idea what components I used. Sorry!

I never use PCBs - they take far too long to design and make. My gear is always at the “prototype” stage.

73

Richard
G3CWI


#10

In reply to G3CWI:

There is no detailed info - and there is unlikely ever to be any. I
build gear for my enjoyment.

That is a pity since I’m sure others would be interested in your designs and also gain enjoyment from them.

I never use PCBs - they take far too long to design and make.

Understood.

Colin G8TMV


#11

In reply to G8TMV:

Roger G3XBM’s 4m transverter looks straightforward. Built dead bug style no PCB is needed and is essentially a junk box special.

I’d build one but I have insufficient time and too many projects yet to finish.

Andy
MM0FMF


#12

In reply to MM0FMF:

I have to reply to this one, if only to inject a little nostalgia! I have a home brew 4m transceiver which I put together in 1977 based on the DC6HL 2m design, published in VHF Communications.

It is all discreet components, of course, and has an analogue mixer VFO, and a hand calibrated dial! It is still working and in use 34 years on, and occasionally drives my home brew 4CX250B linear of similar vintage.

I have thought of taking it on activations (minus linear, obviously :o) but without foreseeing the advent of SOTA, I included an unnecessarily large mains transformer in the case! (hand folded, two part aluminium case, in the style of RL Drake receivers. Ahhh).

Having no processors to guzzle power, it is fairly efficient, and I did take it up a few hills in it’s youth, with a couple of “lantern batteries” to run it. It pushes out around 2W.

This is slightly OT, as the CW facility is still under development (ahem), having unsuccessfully attempted to achieve full break in some years ago…

Maybe this thread will push me into further development!

Adrian
G4AZS