# MDC1200 expirience and issues **URL:** \ **Category:** AllStarLink\ **Created:** [April 30, 2024, 8:44pm UTC](https://community.allstarlink.org/t/mdc1200-expirience-and-issues/21080 "2024-04-30T20:44:57Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Buhalo](https://community.allstarlink.org/letter_avatar_proxy/v4/letter/b/dbc845/32.png) [@Buhalo](https://community.allstarlink.org/u/Buhalo)\ **Post date:** [April 30, 2024, 8:44pm UTC](https://community.allstarlink.org/t/mdc1200-expirience-and-issues/21080/1 "2024-04-30T20:44:57Z")
In some cases, it is very convenient to use the MDC1200 functionality built into the app\_rpt. I use it to control the operating modes of the repeater, to control access to the repeater in RAC mode, and also to run various macros using the rich signaling capabilities provided by the MDC1200 and P25 radios. The main problem is that the decoder built into the app\_rpt app works correctly, but at the same time the encoder is quite primitive and does not even support mdc1200 preambles, which negatively affects signalling decoding on the radio side. The author of the decoder and encoder updated them quite a long time ago, a later version also supports preambles and reduced amplitude sin tables which are more appropriate to app\_rpt usecase. Is it possible to integrate later MDC1200 code into the current allstarlink repository? > **[GitHub - atmatthewat/mdc-encode-decode: Software modem for a specific data...](https://github.com/atmatthewat/mdc-encode-decode)** > > Software modem for a specific data burst format. Contribute to atmatthewat/mdc-encode-decode development by creating an account on GitHub. There is also a more global problem that I encountered. So, when using MDC1200 or tonemacro to manage node connections, after several hours of node operation, significant problems with audio quality arise. The quality drops so much that the node becomes unusable. The problem can only be solved by rebooting the host. The problem also arises when using MDC1200 modes that require delivery confirmation, such as MDC1200 status. When using simple MDC1200 modes, such as PTTID decode or RAC, such problems do not arise. ---
**Author:** ![W2PW](https://community.allstarlink.org/user_avatar/community.allstarlink.org/w2pw/32/2098_2.png) [@W2PW](https://community.allstarlink.org/u/W2PW)\ **Post date:** [May 3, 2024, 10:18pm UTC](https://community.allstarlink.org/t/mdc1200-expirience-and-issues/21080/2 "2024-05-03T22:18:00Z")
Hi. Some basic questions. What’s “RAC” mode? How does one use MDC to fire a macro? Can one use MDC to act as a squelch/repeater access qualifier? Thanks -Pres W2PW ---
**Author:** ![KK6RQ](https://community.allstarlink.org/user_avatar/community.allstarlink.org/kk6rq/32/3511_2.png) [@KK6RQ](https://community.allstarlink.org/u/KK6RQ)\ **Post date:** [March 17, 2025, 7:36am UTC](https://community.allstarlink.org/t/mdc1200-expirience-and-issues/21080/3 "2025-03-17T07:36:02Z")
The answer to your 3rd question is YES, which is the answer to your 1st question (RAC = Repeater ACcess).