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					TEST REPORT                     Analogue Modulator

VAM 420

High Quality
Analogue                                                                                                                •	easy	to	create	analogue	tv	signals

                                                                                                                        •	extremely	good	technical	specifications
                                                                                                                        •	simple	and	fast	programming
                                                                                                                        •	also	suited	for	extremely	long	cables

66 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 09-10/2012 —          — 09-10/2012 — TELE-satellite International — 全球发行量最大的数字电视杂志   67
TEST REPORT                     Analogue Modulator


                                 SPAUN VAM 420 NG PAL
                                    Easy way to create
                                   analogue tv channels

                                                                                                                        ■Ready for the

Generate your own
analogue tv channel system
   When you need to send an               color systems. It is quite sim-            is the VAM 420 NG PAL of           DVB-T. But let’s get back to
analogue TV signal to a des-              ple today to create your own               SPAUN.                             the analogue version, which
tination far away or when you             analogue TV channel. All you                  Interestingly, SPAUN re-        will currently find many more
would like to distribute just a           need is a source of analogue               cently also launched a simi-       uses than the digital version
couple of TV channels, it still           signals (TV camera, VCR, or                lar device, the VAM 420 NG         (there aren’t yet so many
makes sense to use an ana-                just the output of a satellite             DVB-T. Obviously, this device      signal sources with a digital
logue modulator and the old               receiver) and a VSB modu-                  is doing exactly the same as       output).
good PAL, SECAM or NTSC                   lator. One such modulator                  the VAM 420 NG PAL, only in          This twin modulator is care-

68 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 09-10/2012 —
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                                                                                                                        fully finished off as all SPAUN     modulators. One VAM 420             increase the number of ana-        the programming mode. And
                                                                                                                        products. It is designed to be      NG PAL has two sets of inputs       logue channels. Here you           that’s all you need to program
                                                                                                                        mounted either on a DIN rail        (video and stereo audio) and        can also feed a coax from a        and operate this device.
                                                                                                                        or on a flat surface, like a wall   generates two analogue TV           terrestrial antenna to com-           To evaluate the perfor-
                                                                                                                        - either directly or with the       channels. As you can easily         bine the terrestrial signal        mance of the modulator, we
                                                                                                                        help of the included bracket.       calculate, four such devices        with your own two channels         drove it with two analogue
                                                                                                                        SPAUN even offers a perfect         can generate 8 analogue TV          generated by the VAM 420           signals taken from two sat-
                                                                                                                        housing for the VAM 420 NG          channels. SPAUN includes            NG PAL. Observe the advice         ellite receivers (video and
                                                                                                                        PAL: it is called SpaceBox and      a plastic spacer to be used         SPAUN gives in the included        stereo audio). We connected
                                                                                                                        is a 19” rack which can acco-       when mounting the modula-           brochure with technical in-        the SPAUN SPAROS meter to
2                                                                                   4                                   modate either up to 5 or up         tors one next to the other on       structions: when connecting        the output of the VAM 420 NG
                                                                                                                        to 10 VAM 420 NG PAL units.         a DIN rail.                         a terrestrial antenna make         PAL to observe its frequency
                                                                                                                           The modulator can be cas-          Please mind that it is just       sure you insert an amplifier       spectrum. As you can see in
                                                                                                                        caded with three other iden-        a modulator – so if the input       between the antenna and the        our screen shots, the gener-
                                                                                                                        tical units and in such case        video signal complies to the        modulator that has at least        ated signals were extremely
                                                                                                                        you can use a single power          PAL color system, it will not       20 dB input/output isolation.
                                                                                                                        supply unit (SPAUN SNG              be changed and we will get             Programming the modu-
                                                                                                                        12/2000) to power all four          the output in analogue TV in        lator is pretty simple. Only
                                                                                                                                                                                                three buttons are used: Up,
                                                                                                                        1. The SPAUN VAM 420 NG PAL configured to generated two TV
                                                                                                                        signals: one with maximum level, the other with minimum level (-10      Down and Enter. Frankly say-
                                                                                                                        dB). Note that the signals are over 50 dB above the ground noise.       ing, we would prefer if SPAUN
                                                                                                                        2. As above, but now the adjacent channels are used.                    called the last button L/R or
                                                                                                                        3. Test card picture generated by VAM 420 NG PAL.                       something like that. Its func-
                                                                                                                        4. An analogue TV channel demodulated by the VAM 420 NG PAL             tion is just switching between
                                                                                                                        and displayed by the SPAUN SPAROS meter
                                                                                                                                                                                                the left and right channel. In
                                                                                                                                                            PAL. Should it be SECAM, it         the normal mode, you select
                                                                                                                                                            will stay as SECAM. However,        the left or right channel by
                                                                                                                                                            except for the color system,        pressing the Enter button.
                                                                                                                                                            you should also be aware of         The decimal point on the two
                                                                                                                                                            the TV standard that speci-         digit display moves either to
                                                                                                                                                            fies how audio is transmit-         the left or to the right digit
                                                                                                                                                            ted. And here we have a few         indicating in this way which
                                                                                                                                                            possibilities: B, G, D, K, I or L   channel is currently chosen.
                                                                                                                                                            standards. VAM 420 NG PAL           You use then the Up and
                                                                                                                                                            is compatible with all of them.     Down buttons to change the
                                                                                                                                                            It will be perfect for feeding      channel number from S03 to
                                                                                                                                                            analogue tv sets used in Eu-        69.
                                                                                                                                                            rope and many other regions            When you press and hold
                                                                                                                                                            of the world were signals like      the Up and Down buttons si-
                                                                                                                                                            PAL D/K or PAL B/G were             multaneously for one second,
                                                                                                                                                            used and sometimes are still        VAM 420 NG PAL switches to
                                                                                                                                                            in regular days. What it does       programming mode. Now you
                                                                                                                                                            not support are the N and M         can use the Down button to
                                                                                                                                                            standards mostly used in the        travel down the “menu” and
                                                                                                                                                            Americas.                           the Up button to change the
                                                                                                                                                               The VAM 420 NG PAL has           value of the present option.
                                                                                                                                                            two sets of inputs. You can         The options are as follow: TV
                                                                                                                                                            see the familiar yellow/white/      system, fine tuning of video
                                                                                                                                                            red RCA connectors in two           carrier frequency, video/au-
                                                                                                                                                            columns located at the top of       dio ratio (16 or 12 dB), test
                                                                                                                                                            the front panel. In the bot-        pattern generator (on/off),
                                                                                                                                                            tom part of the panel, there        RF output signal (on/off),
                                                                                                                                                            are two F connectors. One           RF level adjustment (from 0
                                                                                                                                                            of them is the output (where        through -10 dB), Audio signal
                                                                                                                                                            two TV channels appear) and         level (from -6 dB through +6       ■A similar device as the VAM
                                                                                                                                                                                                                                   420 NG PAL is the above model
                                                                                                                                                            the other in the input. You         dB), Audio processing mode         VAM 420 NG DVB-T, which has
                                                                                                                                                            can connect another VAM             (mono, stereo, dual). When         recently been launuched by
                                                                                                                                                                                                                                   SPAUN. The features are the
                                                                                                                                                            420 NG PAL to the input to          you are through with all the       same as for the VAM 420 NG
                                                                                                                                                                                                settings, you again press and      PAL, but instead of an analogue
                                                                                                                        ■The SpaceBox by SPAUN solves any problems, where to mount                                                 PAL signal the VAM 420 NG
                                                                                                                        the VAM modules. It can house up to 5 or up to 10 VAM 420 NG PAL        hold Up and Down buttons           DVB-T has a COFDM output
                                                                                                                        units.                                                                  simultaneously and leave           signal.

70 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 09-10/2012 —                                              — 09-10/2012 — TELE-satellite International — 全球发行量最大的数字电视杂志   71
clear – well over 50 dB above             restrial frequency band. We                formance of VAM 420 NG PAL                level and frequency settings.
the noise level. We tested                also checked how it worked                 was brilliant for all the set-            Video to audio level ratio was
both maximum and mini-                    when two adjacent channels                 tings we tried.                           quite close to its nominal
mum amplitude settings and                were chosen to output the                     To give you the idea how               value 16 dB. With such su-
performance at the low end                analogue channels. We are                  great the performance was                 perb performance, you can
and the high end of the ter-              happy to inform that the per-              let us provide you with a cou-            connect the VAM 420 NG PAL
                                                                                     ple of measurement results.               even to a very long coax ca-
                                                                                     See the table below. C/N                  bles without any fear of signal
                                                                                     significantly exceeded the                degradation. This modulator
                                                                                     specification (50 dB) for all             is really a top quality device.

                                                                                                             Min. level setting             Max. level setting
                                                                                          Channel              S03         67            S04       S05         69
                                                                                      Frequency [MHz]        119.25     839.25          126.25   133.25     855.25
                                                                                        Level [dBµV]           80.4       79.1           91.3      91.2       91.2
                                                                                          C/N [dB]            >55.7      >51.4          >57.1     >57.9      >61.8
                                                                                          V/A [dB]            15.1       15.7            17.4      18.1      15.4

                                                                                                                Expert Opinion
                                                                                            Excellent C/N ratio exceeding the
                                                                                            specified 50 dB.
                                                                                            Very good workmanship.
                                                                                    +       Versatile mounting options.
                                                                                            Cascadable with other identical units.
                                                                                            Easy programming.                                       Jacek Pawlowski

                                                                                    –       None
                                                                                                                                                          Test Center

                                                                                      Manufacturer                      SPAUN electronic GmbH & Co. KG, Germany
                                                                                      Phone                             +49-7731-8673-0
                                                                                      Fax                               +49-7731-8673-17
                                                                                      Model                             VAM 420 NG PAL
                                                                                      Function                          VSB Twin Modulator
                                                                                      Number of analogue A/V inputs     2
                                                                                      Frequency range                   110 … 862 MHz
                                                                                      TV standard                       B/G/D/K/I/L
                                                                                      Output level max                  90 dBµV
                                                                                      Output level adjustment           0...-10 dB
                                                                                      Spurious level                    <-60 dB
                                                                                      C/N ratio	                        ≥	50	dB
                                                                                      Input level                       1 ± 0.1 V p-p
                                                                                      Supply	                           12	V,	475	mA
                                                                                      Dimensions                        196	x	106	x	35	mm

72 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 09-10/2012 —