Butchering the Winfast TV2000XP for FM DX

Please consider the risks involved with modifying a tuner before proceeding with any project. The author shall not be liable for any loss or damage whatsoever (including human or computer error, negligent or otherwise, or incidental or consequential loss or damage) arising out of, or in connection with any use or reliance on these instructions.

The Leadtek Winfast TV2000XP is a Peripheral Component Interconnect (PCI) card to receive FM and analogue television broadcasts. The card also provides analogue video capture functionality via an S-video input. At the heart of the card is the Philips FM1216 / PH hm tuner. The module may be used in a number of other manufacturers’ analogue TV and FM cards, including:

  • Hauppauge WinTV FM;
  • AverMedia AverTV Stereo Edition Desktop TV Personal Video Recorder &
  • Conexant Fusion 878A Easy TV.

The tuner includes the following Philips’ integrated circuits:

  • TDA5736;
  • TSA5523;
  • TDA9809 &
  • TDA7040.

Since analogue television is ‘done and dusted’ these cards (below) may be classified as redundant technology. Accordingly, most sell for less than 10 bucks on Ebay!

Card featuring Philips FM1216 tuner © 2007 Whazilla

The card may be used with Dscaler noise reduction software for weak signal detection, such as low VHF band Sporadic E in regions where analogue television is still operational. Because of the wide frequency coverage, Klaus Hirschelmann suggests the tuner offers potential to receive International Radio and Television Organisation (OIRT) broadcasts still on-air in Eastern Europe.

Live recording with TV2000XP

According to Philips:

The tuner [Automatic Gain Control] AGC for both TV and FM radio operation is generated with a novel AGC detector which measures the [Intermediate Frequency] IF signal level directly at the tuner IF output pins. As opposed to the conventional AGC detector, this new circuit allows a higher take-over level and offers superior immunity against tuner overload.

The tuner offers satisfactory strong signal immunity. Performance is markedly better than the E4000, R820T or FC0013 tuners used in a Realtek Software Defined Receiver (SDR) or a Silicon Laboratories’ Si4734 based portable receiver connected to the same rooftop antenna. Philips’ tuner typically features an Image Rejection of 65 decibels for the FM band. In terms of benchmarking, a Yamaha TX-930/950 component tuner features a more favourable 90 decibels. AM Suppression – the ability of the tuner to reject AM signals, is specified at 38 decibels.

Whilst the tuner features interference suppression, the separation of FM stations is not up to contemporary requirements. When Philips Components designed the tuner, Digital Signal Processing (DSP) was at its infancy. These days, DSP based tuners are perhaps taken for granted. Whilst away interstate recently, this blogger noticed that even a cheap TDK Ipod dock supplied in the apartment featured a DSP FM tuner!

Timer Radio Recording with TV2000XP

The scheduled timer recording functions for recording (above) on the TV2000XP is a boon. Therefore, it is a shame that the tuner is not suited to a congested FM dial. When it was used for television recording, the software accompanying this product worked flawlessly.

The tuner does not permit a listener to separate fringe stations 100 kHz apart, and to hear several stations without interference from strong local stations, it was necessary to off-tune 50 kHz to prevent audible interference. Fortunately, sensitivity seemed fine, for example daily reception (a 26 kW broadcast) out to 208 miles (335 km) was possible with a modest combination rooftop antenna without a preamplifier. Sensitivity for a weak signal with a 26 dB signal to noise ratio is 2.24 uV, compared to a Yamaha TX-930 with a more favourable 0.8 uV. Most tuner software (including Leadtek and Hauppauge) features a five segment signal strength meter.

After quite a few drinks one night the author decided that it would not hurt to rip the tuner module open and see what was inside! It was no risk, because a replacement card is dirt cheap. Worst case scenario, if secondhand supplies dissipate, one can simply solder in a new tuner module, pictured below.

FM1216 tuner module © 2013 Max's Depot

The fact the aluminium lid of the Philips FM1216 / PH hm tuner module could be easily plied open was a surprise. What was inside was even more interesting. Staring up at this ‘butcher’ were two 230 kHz Murata ceramic filters and one ceramic discriminator. The block diagram (below) shows the role of the two 10.7 MHz IF filters.

Block Diagram of FM1216 © 2013 Philips Components

To aid easy identification of components (in this case, the existing filters), it is recommended to refer to an online source such as Bruce Carter’s Ceramic Filter page.

Was this ‘elderly beast’ a candidate for a filter butchering? Hell yeah! Hence this article is basically another instalment of the ‘narrow filter modification’ project. It never gets old. 🙂

TV2000XP inside tuner module

Because the rear of the tuner module cannot be easily accessed, the existing wide filters are perhaps best removed from the enclosure… by force! Pliers were – again – used to ‘throttle and crumble’ the existing filters, easily identifiable by the Murata logo. The replacements are soldered in place of the old ones.

The tuner module features a large Printed Circuit Board (PCB) as illustrated on the left half of the photograph above. Even ‘old eyes’ are unlikely to encounter problems with such a simple project. This is a five minute project requiring little equipment, consisting of:

  • general purpose pliers;
  • a soldering iron;
  • solder;
  • desolder braid (optional);
  • philips head screwdriver (optional) &
  • replacement 10.7 MHz filters of one’s choice.

Mike Bugaj is another enthusiast who enjoys ‘butchering’ FM tuners as much as this blogger! He prefers to change one filter first and test performance before proceeding with replacing the other wider filters. This blogger takes the same approach. One of the two 230 kHz filters was removed and a 80 kHz filter soldered in its place. The butchering is not pretty (below), in fact it is possibly one of the ugliest mods ever performed… ‘but she works!’ Stations 100 kHz apart can now be heard, whilst the distortion levels of FM broadcasts remain satisfactory.

80 kHz filter replacement pictured lying flat, E10.7T - FM1216 module

Whilst not mandatory, a preamplifier improves sensitivity. As mentioned above, the module may not be up to component tuner standards for weak monophonic or quieting stereo signals.

Ferrite suppression chokes for RG6Q coaxial cable - TV2000XP card in far rear expansion slot

For the finishing touch, it is recommended to purchase a few ferrite suppression chokes to clip onto the coaxial cable (above) to minimize Electro Magnetic Interference (EMI) problems from a desktop PC. The blogger can recommend jteam Electronic Components. Their chokes (below) were posted quickly from Perth, Western Australia and were very inexpensive compared to retail supplies.

Ferrite suppression chokes for RG6Q coaxial cable

To minimize interference from the desktop PC, so as to maximize FM tuner sensitivity:

  • A CRT computer monitor should NOT be used;
  • Internet routers should be switched off;
  • Remove all unnecessary or unused leads connected to the desktop computer such as USB extension cables &
  • Use RG-6 Quad Shield Coaxial Cable for all connections from the tuner to the antenna wall plate.

A recommended source for replacement 110 kHz narrow ceramic filters is Greg Gortman of Lexington, Kentucky. International carriage is available from these sources. Prior to publication stocks were available.

Programme details in RDS Spy © 2013 Jan Kolar, Czech Republic

Klaus Hirschelmann notes that the tuner module features an Multiplex Output for RDS use. Whilst this blogger has not tried it yet (perhaps after the Ashes test cricket series) the Data and Clock signals (found on pins 13 & 14) can be fed via a shielded cable to the Line Level Input on a sound card. In theory, this should enable RDS decodes with RDS Spy software, illustrated above and below.

Sound card input in RDS Spy © 2013 Jan Kolar, Czech Republic

For those craving more experimentation, H. Chew suggests the Philips tuner can also be used as an SDR under a Linux operating system. Polish enthusiasts have even built the module into a ‘stand alone’ RDS component tuner!

Specifications quoted above may not necessarily be indicative of performance. There is nothing preventing manufacturers from using different test signals to make measurements in an effort to improve performance specifications for marketing purposes.

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