DYNAS
Dynamic analog filtering and tuning for improved FM reception.
DYNAS, short for Dynamic Selectivity, is an analog technology that dynamically filters and tunes FM radio signals to enhance reception in difficult conditions. The system is based on the same principles as the In Channel Select (ICS) system developed by H.u.C. Elektronik. The core tracking filter concept was first conceived by German engineer Jens Hansen in 1982, prototyped as High Select in summer 1983, and led to Hansen leaving Bosch/Blaupunkt to co-found H.u.C. Elektronik with Klaus Müller-Catito in 1984, funded by Berlin innovation grants. After failed licensing talks with his former employer, the system was marketed in the early 1990s as DYNAS by Telefunken electronic (a spin-off of AEG-Telefunken and DASA, formed in 1992). Telefunken, together with the former AEG-Telefunken Halbleiterwerk in Heilbronn, also produced integrated circuits for the system: the TEMIC/TFK U4290B (stand-alone FM IF DYNAS system in a 68-pin PLCC package), the U4291B (DYNAS coprocessor), and the U4292B (software-controlled DYNAS system in a 44-pin SSO package).
Compared to conventional receivers, DYNAS offers more than 26 dB better selectivity and roughly twice the sensitivity (a 6 dB improvement), nearly doubling the reception area and enabling reception of even extremely noisy stations. This performance comes from an adaptive IF filter bandwidth and real-time dynamic tracking of the IF filter’s center frequency. With a transmitter spacing of 200 kHz, undisturbed stereo reception is possible; with 100 kHz spacing, largely undisturbed mono reception remains achievable.
The technology was adopted in several high-end FM tuners, including the analog Burmester Tuner 915 (1991) and the digital synthesizer tuners Onkyo Integra T-4970 (1992) and T-488F (1993). It also appeared in various car radios, such as the Alpine 7619R (1989), Alpine 1310R/3681 (1990), JVC KS-CG10 (1992), Clarion CRX121R (1993), CRX123R (1993), CRX121RM and CRX123RM, Gelhard GXR 990S (1993), and Conrad Soundcraft AR6800 DYNAS, all of which face challenging and rapidly changing reception conditions.
Similar technologies include the In Channel Select (ICS) system by H.u.C. Elektronik from 1984, a DYNAS predecessor for narrowband FM receivers based on the High Select tracking filter developed by Jens Hansen since 1982. ICS improved selectivity by about 20 dB and sensitivity by about 6 dB.
- Developer
- Telefunken electronic (a spin-off of AEG-Telefunken and DASA)
- Origin
- Based on the In Channel Select (ICS) system by H.u.C. Elektronik, originally conceived by German engineer Jens Hansen in 1982
- First prototype
- High Select, summer 1983
- Marketed from
- early 1990s
- Selectivity improvement
- more than 26 dB
- Sensitivity improvement
- 6 dB (twice as good)
- Integrated circuits
- TEMIC/TFK U4290B, U4291B, U4292B
Lore & Background
The DYNAS system is based on the same principles as the In Channel Select (ICS) system by H.u.C. Elektronik. The novel tracking filter arrangement was originally conceived by the German engineer Jens Hansen in 1982. The concept was prototyped as High Select in summer 1983. With funding from innovation funds of the city of Berlin, Hansen left Bosch/Blaupunkt to start, with companion Klaus Müller-Catito, his own company H.u.C. Elektronik in 1984. When licensing negotiations with his former employer failed, the system was marketed in the early 1990s as DYNAS by the German Telefunken electronic, who, with the related TEMIC/TFK, also designed integrated circuits implementing the system: the U4290B (stand-alone FM IF DYNAS system in 68-pin PLCC package), U4291B (DYNAS coprocessor) and U4292B (software-controlled DYNAS system in 44-pin SSO package).
The technology achieves its performance through an adaptive bandwidth of the IF filter and by dynamically tracking the center frequency of the IF filter in real-time. With a transmitter spacing of 200 kHz, undisturbed reception in stereo is possible; with 100 kHz, largely undisturbed mono reception is still possible. Similar technologies include the In Channel Select (ICS) system, the Active Real-time Tracing System (ARTS) by Pioneer, Super Sound Tracing (SST) by Sony, and Blaupunkt's Sharx technology.
Reader's Guide
DYNAS was adopted in several high-end FM tuners and car radios, particularly those affected by difficult and rapidly changing reception conditions. Examples include the analog Burmester Tuner 915 (1991), the digital synthesizer tuners Onkyo Integra T-4970 (1992) and T-488F (1993), and car radios such as the Alpine 7619R (1989), 1310R/3681 (1990), JVC KS-CG10 (1992), Clarion CRX121R (1993), CRX123R (1993), CRX121RM and CRX123RM, Gelhard GXR 990S (1993), and Conrad Soundcraft AR6800 DYNAS. The system's significance lies in its ability to dramatically improve selectivity and sensitivity in FM reception, enabling reception of weak or noisy stations that conventional receivers could not handle. Its adaptive IF filtering and real-time center frequency tracking set a benchmark for analog dynamic selectivity. The technology also influenced later digital solutions, such as Blaupunkt's Sharx, which initially used a bank of switchable analog ceramic resonators before moving the IF filter into the digital domain around 2000. DYNAS remains a notable example of analog signal processing innovation in radio electronics.
Did You Know?
- DYNAS stands for Dynamic Selectivity.
- The system was originally conceived by German engineer Jens Hansen in 1982.
- DYNAS provides more than 26 dB better selectivity and 6 dB better sensitivity than conventional receivers.
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