Can anyone tell me the name of the 12 volt power pack that was being praised on here a few months ago. I need to buy one.
With thanks in anticipation
from Charlie
In reply to G0PZO:
Can anyone tell me the name of the 12 volt power pack that was being
praised on here a few months ago.
I’m not sure whether it is what you are thinking of, but somebody did mention the Tekkeon myPower ALL (two models, MP3300 and MP3400). It has some nice features, but I can emphatically NOT recommend it for SOTA.
The problem with it, in a nutshell, is that it incorporates an internal DC-DC converter. Whilst this is great for keeping the voltage stable as the battery discharges, it generates the most appalling RF hash. On 2m FM, we found that it could blot out anything weaker than S9+, and Caroline found herself having to give silly reports like 39.
I’ve been experimenting since we got back home, and I found that a ferrite ring choke in the power cable will reduce the interference at VHF to manageable levels, though there is still some direct radiation from the battery pack. However this proved ineffective at HF. I’ve been doing a bit of portable operation on 20m to 10m, and the FT-817 is useless on these bands with this battery connected.
I am still looking for something better myself.
In reply to M1MAJ:
Martyn
That’s odd. I think that several SOTA people have them and seem to like them. Is yours faulty I wonder? I dont have one so can’t comment from personal experience.
73
Richard
In reply to G3CWI:
Is yours faulty I wonder?
Interesting question. It seems to work in the sense of producing the output it should, and obviously it must contain an oscillator, so I assumed it was an inherent feature of the device. I very nearly bought a second one, but cancelled the order when I discovered the problem.
It comes with a short coiled cable which must have some inductance, and the interference is not as bad if I use this. However I find this cable dreadfully inconvenient and normally use a cable I made up for myself with a PowerPole on the end. This is the cable that I’ve put the choke on.
Hi Martyn
Might be worth checking yours out as Chris M0JRQ was extolling the virtues of them to me a while ago… says they knock spots off anything else he’s used and didnt mention RF hash etc.
73 Marc G0AZS
In reply to G0AZS:
Might be worth checking yours out
How?
Hi Martyn
Well I would think comparing with another one would seem a good start… anyone you know nearby got one? Is it still under warranty?
73 Marc G0AZS
In reply to G0AZS:
anyone you know nearby got one?
Not that I know of. There’s one person who MIGHT have bought one after I mentioned it on the local repeater - I’ll ask.
Is it still under warranty?
It should be, but “it does what it says on the tin”, so I don’t really think I can say it has a fault without more evidence. Perhaps it fails to meet the EMC standards implied by the CE mark, but I don’t have the test equipment to verify that. We all know that lots of consumer equipment meets the standards and still blots out amateur radio reception (Radcom, passim).
In reply to M1MAJ:
There’s one person who MIGHT have bought one after
I mentioned it on the local repeater - I’ll ask.
If he bought one on your recommendation maybe you don’t want to speak to him!
73
Richard
In reply to M1MAJ:
I have one of these and I haven’t noticed any hash from it.
I’ve just tried it under load with the rubber duck on my VX7 inside the curly cord. There was a slight signal on 143.8 but nothing else anywhere between 143 and 146. I surmise, therefore, that yours is faulty.
Roger G4OWG
In reply to G4OWG:
I’ve just tried a similar test with my VX7. I don’t hear much, as the interference sounds much the same as the normal background hiss on FM. However I can certainly see it on the S meter. It goes to S9 at times.
Could somebody with one of these batteries try putting it next to an ordinary domestic AM radio with a ferrite rod antenna? With mine supplying a moderate load (charging my VX7) it totally blots out anything on medium wave within a few inches of the battery. Weak stations are affected much further away. My Sony ICF7600D and a cheapo Superdrug radio seem to be affected equally.
In reply to M1MAJ:
A few things spring to mind here.
-
Cost engineering or someone decided more profit could be made by no longer fitting the filter components. The other example may have come from an early batch when more filtering was fitted.
-
Broken connection or dry joint on some of the filtering components. Worth opening the unit up and inspecting the circuit board.
Andy
MM0FMF
In reply to MM0FMF:
Worth opening the unit up and inspecting the circuit board.
I don’t think this would be a reversible operation. The case looks to be glued/welded to me. There are certainly no visible screws.
In reply to M1MAJ:
Next to very cheap Pacific clock-radio (ferrite and short wire) absolutely no affect whatsoever. Driving VX5 with volume up full.
Roger G4OWG
In reply to G4OWG:
Next to very cheap Pacific clock-radio (ferrite and short wire)
absolutely no affect whatsoever.
Thanks for that. It does indeed sound like my MP3400 is faulty. Whether I will be able to convince the supplier though is another matter. A few more data points from other owners might be helpful.
A further followup on this thread about the myPower MP3400 battery pack, and my report that it generates RFI.
Various people said they had no problem with this battery, and suggested that mine must be faulty. I therefore decided to risk getting another, with the ultimate aim of getting my original replaced if I could demonstrate that it had a problem.
Unfortunately I have to report that the new one is just as bad.
I can only assume that those who report the device to be clean are referring to a different product. Perhaps there has been a design change or something.
Whatever, I stand by my original comment - I urge caution in choosing any battery pack containing an internal DC-DC converter for SOTA work.