flat batteries and a moody boost gauge

[fritzo]

Hi all, Ive been having issues with my battery losing its charge for a good while now, the car gets used once a week and whilst I try to give it a good run after a few weeks the battery eventually die’s. I changed the battery around a year ago and have always assumed that its just the been down to the lack of use and/or the cold weather and if I’m honest, have been too lazy to actually rectify the problem.
The problem I have aside from the goddamn frustration of having a flat battery the one time a week I use the car, is that in preparation for some work that I’m planning to have done I’ve brought a oddyssey PC680 and given the issues I had with a full size battery Im a little dubious about my new comedy sized battery lasting more than a few days.
So I’ve got to thinking whether there is actually something wrong with the charging system and the battery is draining back through the alternator or whether its maybe earth related as from what I understand they tend to be a weak point.
Has anyone had similar issues at all?
Also does anyone happen to know what the standing parasitic loss is with an alarm/ immobliser fitted as I’m gonna stick a multi meter on it at the weekend and it would be handy to have something to compare it against.
Also my boost guage, whilst working as in it rises and falls like it should do, for some reason is now reading a half bar over constantly in vacuum and in boost. Its an electronic greddy effort and again has been fitted a year and has been playing up for the past 6 months (like I said I’m lazy :spank) I have a matching greddy water temp gauge which works fine. The car is boosting fine from what PFC commander reads.
Could this possibly be an electrical issue?
Cheers in advance
 
fritzo