DSL/ADSL filters.
June 6, 2015 8:58 AM Subscribe
Will a DSL filter do the same job as an ADSL filter? I've tried googling but ironically there's a lot of noise.
I bought a used filter this morning and it wasn't until I got it home that I realised it said DSL rather than ADSL. How important is the A?
I bought a used filter this morning and it wasn't until I got it home that I realised it said DSL rather than ADSL. How important is the A?
The A stands for Asynchronous (your download speed is faster than your upload speed). It's the DSL part that's the important bit.
posted by Solomon at 9:12 AM on June 6, 2015
posted by Solomon at 9:12 AM on June 6, 2015
It's not necessarily the same thing. Filters which worked for DSL/ADSL/ADSL2 (with singalling up to 1.1MHz) don't work well for ADSL2+ (what you're probably getting today as "ADSL", up to 2.2MHz) or VDSL (what you're getting if your line is relatively new and you're within ~4k feet of the CO).
And it has been observed that filters can wear out over time.
Try it. If it works, great. However, most (non monopoly) ISPs are pretty liberal about handing out filters, and every time I get a new modem I end up with a handful of the damned things, so they can't be that pricey.
posted by straw at 9:15 AM on June 6, 2015 [1 favorite]
And it has been observed that filters can wear out over time.
Try it. If it works, great. However, most (non monopoly) ISPs are pretty liberal about handing out filters, and every time I get a new modem I end up with a handful of the damned things, so they can't be that pricey.
posted by straw at 9:15 AM on June 6, 2015 [1 favorite]
Response by poster: So just to check it will work exactly the same way as the modern ADSL filter we have on the telephone in the living room?
posted by feelinglistless at 9:16 AM on June 6, 2015
posted by feelinglistless at 9:16 AM on June 6, 2015
Response by poster: Sorry asked before seeing Straw's comment.
posted by feelinglistless at 9:18 AM on June 6, 2015
posted by feelinglistless at 9:18 AM on June 6, 2015
I don't recall if it is, but check the label on the filter to see if it shows what frequencies it works with. You can then look at the diagnostic page on the modem to see what frequencies it is using and find out if they are compatible.
As long as you don't pick up a phone and nobody calls you can run the modem without a filter temporarily if necessary.
posted by wierdo at 9:59 AM on June 6, 2015
As long as you don't pick up a phone and nobody calls you can run the modem without a filter temporarily if necessary.
posted by wierdo at 9:59 AM on June 6, 2015
the modern ADSL filter we have on the telephone in the living room
If this possibly-dodgy DSL filter is going to be one of two the same line, use the modern one to connect your modem and one phone to one socket, and use the possibly-dodgy one between the second phone and its socket.
If your modem has a socket of its own, and doesn't need to share one with a phone, then you can just wire the modem straight to the socket without needing a filter. The filters exist to keep old-school phone equipment away from the ADSL signal, not to keep the modem away from the voice signal (which it will not affect). However, this does mean that the modem itself, rather than a cheap filter, will be in the direct line of fire for any lightning-induced spikes on your phone line.
posted by flabdablet at 10:28 AM on June 6, 2015
If this possibly-dodgy DSL filter is going to be one of two the same line, use the modern one to connect your modem and one phone to one socket, and use the possibly-dodgy one between the second phone and its socket.
If your modem has a socket of its own, and doesn't need to share one with a phone, then you can just wire the modem straight to the socket without needing a filter. The filters exist to keep old-school phone equipment away from the ADSL signal, not to keep the modem away from the voice signal (which it will not affect). However, this does mean that the modem itself, rather than a cheap filter, will be in the direct line of fire for any lightning-induced spikes on your phone line.
posted by flabdablet at 10:28 AM on June 6, 2015
And I just noticed: I've got a back of ADSL2+ filters, that came with an ADSL2+ device, that are labeled "DSL". But I also know that when I switched from AT&T ADSL to Sonic's "Fusion" ADSL2+ product, about 4 years ago, I had to switch out my filters. So try 'em, see if they work for you.
posted by straw at 3:57 PM on June 6, 2015 [1 favorite]
posted by straw at 3:57 PM on June 6, 2015 [1 favorite]
This thread is closed to new comments.
posted by GuyZero at 9:01 AM on June 6, 2015 [3 favorites]