Telephone Dialup Frequently Asked Questions / Troubleshooting / Software Versions
All our Dialup systems are designed for trouble free operation over an extended period of time and so problems should be rare. Answers to all questions asked and known issues are described below:
Will a Dialup work on an ADSL Line?
- Yes. Since the Dialup is exactly equivalent to a normal telephone, it will work on an ADSL high speed digital line. Be aware though that additional bandwidth filtering is used and this may degrade audio quality slightly.
What happens if I cough - Can anyone hear it?
- No, the system is designed specially so that nothing you do or say will be reflected back to the venue and broadcast over the sound system.
How long will I stay connected?
- If you ring the venue, you will stay connected for as long as you wish. When finished, simply hang up the telephone exactly the same as if you had just finished speaking with auntie Ann.
Who pays for the call?
- Whoever makes the call. In the example above, you do since you rang the venue. Given the latest price wars between telephone companies, you might even get connected for free at weekends and during evenings (check your Telco).
Why does my Dialup disconnect itself sometimes?
- For manual calls (ie dialed out) on TDS1 units supplied prior to 2002 only - Try removing the link (small red or blue plastic component) fitted next to the microprocessor chip (the black bit with 28 legs) shown on the Telephone Dialup Installation diagram as 3Hr Timer Option.
- A couple of sites report this effect where the Dialup
unit drops out on an apparently random basis (Auto mode only). Closer analysis shows that this only happens
when the unit is set to give too high an output level in an attempt to correct low volume at the
receiving end. In fact the internal microprocessor is constantly looking for a "Line
Disconnect" signal from the exchange when the Dialup is active (only in auto answer mode) and if
the audio sent from the Dialup is set far too high, this tricks the microprocessor into
clearing down. This is a safety precaution and prevents massive overload at the telephone
exchange. Solution: Buy a better quality loudspeaking telephone at the receive end that has
- Network faults. The telephone network is subject to a small percentage of random failure
where the call will fail for no apparent reason. Failure can be at any point during the setup, during
the call itself or at cleardown time and has nothing to do with the Dialup unit or the caller. A typical
scenario would be that the system is connected and working fine for a period of time and then the audio
fails and does not come back on. The only solution to this is to clear down (hang up) and redial the
connection. A failure rate greater than 5% (1 call in 20) is symptomatic of a traceable fault and should
Why will my Dialup not Clear down when I hang up (Auto Mode)
- Some exchanges notably NTL have a non standard cleardown sequence where the industry standard K Break signal
is missing. The only work around for this problem is to switch off your Dialup unit at the conclusion of the program. If you wire up the mains as shown elsewhere, this will happen automatically - whenever the sound system is switched off.
What happens if there is a power surge or power interuption
- Interuptions to the power supply of a couple of seconds or more will automatically disconnect the Dialup as a safety precaution. Calls will need to be re-established once the power is back on. Large power surges may blow (but unlikely) the internal fuse within the Dialup - see the next section.
Unit dead - no power light on the front panel.
- Check the following in this order:
- Mains plug fuse (3 or 5A Max) and 13A socket live.
- Internal fuse adjacent to the mains transformer close to the LNE connector. This is a 20mm Anti Surge type rated at 100mA (0.1 Amp). If blown, replace with a similar fuse. DO NOT put a higher value fuse in - this will invalidate any guarantee and likely lead to more damage. If the replacement fuse also blows - return the unit for service.
My Dialup is switched on (green light OK) but not responding:
- Switch the Dialup off, wait 10 seconds and switch back on again. Retry and take particular notice of the Red Active light(s). At switch on it flashes once (Automatic) or twice (Manual). If OK and the Dialup now operational you have experienced a short mains failure and your Dialup is OK. If OK but your Dialup is still not responding try unplugging the telephone line cord from the Dialup and test with a known working telephone. If the telephone does not work - either the line or cord is faulty. If the telephone works OK, reconnect the Dialup and make sure that none
of the external wiring (remote switching or display) is faulty and as a last resort try testing the line fuses as described above in TDS Testing. If all of this seems OK you will need to E-Mail us with precise details your installation and problem.
There was a storm outside and my Dialup won't work - Lightning Damage
- The Dialup system has the latest protection circuitry but this will not prevent damage due to a direct lightning strike and in this case your Dialup will need to be returned for a non warranty repair. However, a surge along the telephone line from a "near miss" may blow one or both internal line fuses. These are small rectangular plastic components marked 100mA, and are fitted immediately behind the blue 470nF capacitor which is behind the telephone input socket. The fuses are a plug in type and can be removed for verification. Test with a meter set to Ohms (Resistance) and expect a reading of 4 to 5 Ohms ie a short circuit for each fuse. There are two fuses for each line.
Upgrades - I need some new function(s)
- The TDS1 and TDS2 were designed in response to input from many different sources and have all the facilities originaly requested. However, we are always willing to listen to new ideas and suggestions as to how the products can be improved be this a new option, better instructions etc.. Please let us know your thoughts.
- Every hour, your TDS1 / 2 executes 3600000000 (Three thousand six hundred million) instructions - literally doing a million things a second!
- The printed circuit board took 2451 minutes exactly to design.
- 38% of the total time connected is spent asking questions..What's changed?..How long have I been on?..Am I OK?....!
Dialup Home.....TDS1 Instructions.....TDS2 Instructions....Environmental Section
© 1994-2019 DTSystems. All Rights Reserved.
Designers and Manufacturers of Electronic Equipment.