There is a group of hams that have formed a global PBX called Hamshack Hotline, that allows hams to use VOIP phones to connect to each other.  The service is free (donations are encouraged).

After checking their website, it appeared that a Cisco SPA525G2 was especially easy to provision.  This phone is often available on the used market via eBay.  Prices seem to run from the $30 to $50 range (shop around for sure).  The provisioning process is simple: fill in a service ticket with a copy of your original license and a photo of MAC address of the phone.  The most difficult part was discovering the internal network address assigned by my router.  I expected it to identify it as Cisco, but it didn’t. In my case it began with the letters “spa” (the first three letters of the model name), and was followed by the MAC address.  Within a few minutes I had a desk phone (great speaker phone too) on the Hamshack Hotline network.

A Cisco SPA525G2 connected to Hamshack Hotline (chatting with W2DAN on the speaker phone)

I was surprised to find that Hamshack Hotline can connect to our club’s W1SYE repeater.

Slightly random… I have a Cisco SPA504G VoIP phone which I acquired ages ago and connected to Hamshack Hotline back when the UK still got 5 digit numbers.

The phone isn a 4-line one and subsequently I got a Hams over IP number for line 2, then an extended freedom network number on line 3. After that the phone sat for ages with only the three lines in green, waiting for a fourth.

I did consider buying a VoIP service to transfer our POTS number to once we upgraded to FTTP and lost the copper line. But then, all we used the landline phone for was ignoring junk calls, only ever making calls using my mobile phone which has free minutes and SMS, or using WhatsApp. So the landline went.

And still that fourth line was dark, just sitting there.

Along came CNet. I have had an interest in all things telephony and telegraphy from an early age. I always wanted a small mechanical PABX – I still don’t have one but I do have an eye out for a couple of old dial phones from my childhood. And that’s where the interest in CNet came from. Having investigated further I realised I could use that fourth line for access, and so it happened.

4 lines green…