Flash issues...

I took some low-light photos and used my trusty flash. After developing it doesn't seem to be working like I want. Most of the photo is very dark. Almost as if there was no flash. I've been using a diffuser over the flash lately and in my first test photos after I got it, it worked fine from some 5 feet away... But the photos I took later didn't seem to be the same results. Some distances were longer, but some were 7 feet or so, and it was still dim.

Maybe I need to brush up on my flash work? And I don't mean Macromedia...

Any good refreshers online that I can read? Or maybe some good quality posts/articles here on APUG?

We need more 'Technical Details' such as WHAT is 'your Trusty Flash' make ? Have you checked that you have the correct maximum shutter speed allowed to synchronise with your camera ? I started in the 1950's with flash BULBS and used the 'Flash Factor' system to work out the aperture to use according to the distance -- then I got a Braun Hobby in Germany in about 1957 which was an electronic flash and found the flash factors were not accurate unless a lot extra development was given to the films. then I got a Mecablitz 45CT1 with the 'Magic Eye' automatic exposure but THAT is not accurate either all the time ? I have to recognise the SUBJECT I am taking and correct as I would with continuous light photography -- for example : people in the CHURCH or hall will come out OVER-Exposed as the magic eye reads a lot off the dark background if they are away from a background -- also outdoors at NIGHT faces will be OVER -exposed unless you use a much smaller aperture than flash tells you . UNDER-exposure could be caused by not setting the flash to correct ASA film speed or having people against a WHITE background.

Ah, okay. Well I'll scan an example or two and upload the exact model no. when I get home.