Hi, sorry I havn't been on much to answer any questions. Had rather a lot on in life (bit of an understatement
)
The reason why 612 KHz is highlighted as the 1st place to look for REIN is that its the next major harmonic over the 300 KHz frequency which is the key foundation channel that DSL works from (when your modem/router syncs) Then DSL works around the avalable frequencys up from there to send chunks of information. It's like listening to lots of radio stations all at the same time then combining all that info to get a bigger picture, which is what your modem is doing.
By next harmonic I mean just the same way as this crops up in sound/music. Remember at school having radio waves demonstrated by a piece of string swung like a skipping rope or a slink slid side to side so you get a wave. Double the frquency of hand movement and you get 2 waves along the same string/slinky. Its the next harmonic. Just as musical notes repeat themselfs but in the next octive up etc. 306khz is the key frequency for dsl, but any domestic mw radio dosn't have its range down that far, so we use 612KHz as the next harmonic.
Strong interfernce in other frequencies can also have strong effects for dsl. Its like trying to have a conversation with someone whilst loud music is blearing on the back round. The 444b is essentialy a normal radio, but it broadcasts a whole spectrum of frequencies all at the same time rather than one norrow band as your radio would do. (you only want to listen to one station at a time on the radio). Yes a directional Aeral would help. There's one within BT openreach that fits on the 444b and no one knows where it is ! (crazy I know, Ha ! finaly I can say this.) Otherwise there are directional aerials with a spectral anlyser. They cost a huge amount and the only one I ever saw lives down at the labs in Martlesham. Oh would finding REIN be oh so much simpler with that lovely gadget. Between the 444b and a MW radio I usually found the REIN source with a MW radio much more easly. If anyone want to hear the dsl signal, tune your car radio to 612KHz and each time you drive under a dropwire with a dsl signal then you should hear the noise of the signal as you drive under ther wire.
As for your REIN engineer comming back to look for the source later, your lucky. managerswithin BT do not understand you often need to do this with a REIN fault and no allowance is made for this in the system. and He may well be chased up by his control or managers to find out why he's not on his next task. Offcom hasn't made any allowance for REIN faults so BT dosn't have this fully organised. In fact it could be argued that the the whole REIN proccedure is run by BT openreach as a charitable gesture as accounting wise its a money pit that comes off the company profit margins for whats usualy a problem caused by 3rd parties. the Enginneer is the one who'll get it in the neck. Interesting to see how its arranged in the US. The local main equivalent of BT has a BIG van full of kit for this problem.
