Telephone Experts Please - What Else Can I Try?

[TheScullster]

Hi all

My mother decided she wanted to go cordless and selected tbe BT710 Freestyle - big button twin set. Pre-charged it over Friday and took it round and hooked it up Saturday morning. There is significant interference heard (in between a crackle and hiss) which is not present with a corded phone.

First question - are these cordless phones more susceptible to line noise than corded versions or does this have to be external local interference getting in between the base and the handset?

The master socket and phone base unit is located in the hallway of a standard 3 bed semi, close to the front door.

My diagnostic measures so far include:

Removing the master socket faceplate and plugging the phone into the internal master socket - no change Moving the base as far from the master socket as the telephone lead would allow (approx 2m) - no change Plugging the base into the only extension socket (upstairs) rather than the master - no change Powering off the router which shares the splitter with the phone - no change Swapping the splitter for another not-new splitter - no change

My mother talking to the neighbours - they have a cordless phone and do not experience the same problem.

The only thing I can think of that I haven't tried is checking the unit works on another line, or taking our phone round and trying that on her line. The reason that I don't immediately suspect the phone is that, whilst trying to set this new model up, ISTR they tried a cordless phone years ago and gave up on it because of the interference.

Is there a measuring instrument available for hire perhaps that can check for sources of interference?

Having tried the phone and base unit in an upstairs room (and still noted the problem) I would have thought this would eliminate the possibility of interference from a specific local device. I think the phone line comes in over head, so shouldn't pick up noise from the main power supply to the house.

Can anyone suggest other measures to identify the cause please?

TIA

Phil

[Bert Coules]

How about trying the phone in a different house? If the problem persists it would suggest a fault in the phone itself.

Bert

[TheScullster]

"Bert Coules" wrote

Thanks Bert

Yes I has sort of covered that with "The only thing I can think of that I haven't tried is checking the unit works on another line, or taking our phone round and trying that on her line."

But the distant memory of them having tried a cordless phone years ago and having a similar experience led me to post for other possibilities.

Phil

[Mark]

I would suspect the phone too. The modern ones should not be that susceptible to interference anyway.

[Dave Liquorice]

DECT is not as clear as a direct wired phone. Our Philips has a definate but low level background hiss and speech quality is a bit "raspy". No crackles unless there is a line fault but they show on the wired phone.

You seem to have pretty much eliminated everything other than the cordless phone itself. I think you either need to take it to another line elsewhere and test it again or reject it as faulty for a replacement/refund.

How much do you want to pay and do you have the skills/knowledge to interpret what it tells you...

[Mike Tomlinson]

En el artículo , TheScullster escribió:

AM radio. Turn the tuning knob through the full range until you find the interference, then walk around the house to locate the source (it'll get louder as you get closer)

My bet would be an iffy CH or fridge thermostat, or a loose electrical connection somewhere.

[Dave Plowman (News)]

I have several DECT phones here, and although perhaps not quite as 'clean' as a perfect cabled one I doubt many would notice. If anything they would be likely to reduce line noise, not increase it. Of course they may introduce some noise by themselves.

Try it in another house. If it works fine there, likely interference of some sort - although they're pretty immune from this.

[The Natural Philosopher]

I have never ever heard decent quality out of ANY DECT phone. They also can and do interfere with ADSL. and wifi.

[TheScullster]

"Mike Tomlinson" wrote

Thanks Mike

Would you expect the CH or fridge stat to cause interference through the entire house? Would this interference be "getting in" via wiring between masterbox and base unit, or interupting the wireless handset-to-base unit signal?

Phil

[Mike Tomlinson]

En el artículo , TheScullster escribió:

It can do, yes. Note that this is just one possible cause; there are many others, including a possible faulty phone as already suggested.

[Geo]

Is the problem still there with the phone unplugged from the line and an internal call beteen the two handsets?

You /do/ have an ADSL filter in the line to the phone?

[TheScullster]

"Geo" wrote

Nice idea Geo - I'll investigate that one.

Yes - tried two different ones.

Ta

Phil

[Dave Liquorice]

A "good" one will cause interference over quite an area, several neighbours sort of distance in a typical urban neighbour spacing.

But this isn't likely to be the cause of a constant(?) crackle on a DECT phone. Thermostats normaly just make a big single splat or arc over a period of a few seconds with the sound changing as the arc gets longer before finaly breaking.

[Peter Parry]

Noise between the base and handset on a DECT phone manifests itself as periods of silence, not of noise.

The first thing to do is to take a standard wired phone around - plug it in and see what that sounds like. There is no point in pursuing more esoteric solutions until you have done this.

Analogue cordless phones were very noisy, DECT are not.

[Dave Plowman (News)]

They had also often very poor audio quality.

[tony sayer]

In article , Mike Tomlinson scribeth thus

Humm .. Isn't the current crop of DECT gear up on 1800 odd MHz?..