Plain vs. thermal paper . Cheaper plain-paper fax machines use thermal printing technology, but print on plain paper. Most desktop fax machines transmit at 9600 Kbps. At that speed, it takes about 15 seconds to send a page. Newer laser fax machines transmit at up to 36.6 Kbps, but these are still too expensive for home or small office use.
Fax machines store incoming and outgoing pages in memory.
This lets the machine send pages faster, especially if you want to send the same page to more than one person. The unit can also save an incoming fax in memory if it runs out of paper, and then print the fax when you put paper in. You should shoot for at least 512KB of memory, which can store 20 to 25 pages. Other features . Besides speaker phones and digital answering machines, newer faxes often include such telephony features as caller ID, a distinctive ring that enables it to distinguish between a human or fax machine call, auto redial, fax forwarding and speed dialing.