Technical Aspects of Ecos del Torbes

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Technical Aspects of Ecos del Torbes
The following comments on Ecos del Torbes are from e-mail from Bill Sitzman. Bill is a long-time broadcast professional and consulting engineer. He may be reached at (insert @ in place[NO-SPAM]) ibcengineering[NOSPAM]juno.com

January 25 2001
I found an August 2000 e-mail from you in my Cumbre notes about Ecos del Torbes and have enjoyed finally seeing photos of the station. Many, many thanks for documenting such a fine station. We listen to it regularly and prefer it to our understaffed satellite-glut local stations.
Except for the 9640 one-kilowatt unit, the Ecos del Torbes 780 kHz 50 kW transmitter was instantly recognised as a Harris MW-50A, which is a pulse to amplitude design run by many of the US clear channel stations. The 4980 kHz 10 kW transmitter is a Harris BC-10H broadcast transmitter, which uses solid state low power stages and 3X2500 tubes in the modulator and final stage. The BC-10H also has resonators and traps at the third harmonic to square up the final stage plate current and this raises efficiency to about 87%!
Ivan Escobar is an engineer after my own heart, as I also ran a Harris AM transmitter when I was a station owner. If you ever confer again with Senor Escobar, tell him his transmitter building interior is cleaner than many US stations and I am very pleased with the excellent fidelity of YVOC! It sounds great on our Watkins-Johnson precision HF receiver in our office, which has a bandpass of better than 8 kHz within 1 dB. You can also tell him by now I have been a listener to Lo Ques de Noche Recuerda for 31 years.
Thanks again, Don, for your fine reporting in Latin America and especially for such informative photos.
January 26 2001
Harris moved on from the BC-10H and MW-50A to the DX -10 and DX-50 digitally synthesized AM (and shortwave) transmitters, but still include the SX-1 through SX-5 and Gates One through Gates Five solid state 1 kW through 5 kW transmitters. These solid state transmitters have final stage efficiency in excess of 90% and sound as clean as FM. Nonetheless, there are still many superb sounding MW-50A's and BC-10H's still in service and hence Ecos del Torbes is among excellent company.
Regarding Ecos del Torbes, our database lists YVSC (9640) as authorised for 10 kW. Does Ivan Escobar have any plans to increase its power from 1 kW? Also, the photo showing the multi-element shortwave antenna, presumably for YVOC based on my received signal strength, suggests it has a reflector behind it and a shorter director element in front. That should give about 3 to 5 dB gain. The effective power in our direction from YVOC may be close to 30 kW. Again, just a conjecture from the photo.
Best regards,
Bill Sitzman
Consulting Engineer

This website is maintained by Don Moore,
Association of North American Radio Clubs
DXer of the Year for 1995.
My Address Is In This Graphic

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Technical Aspects of Ecos del Torbes The following comments on Ecos del Torbes are from e-mail from Bill Sitzman. Bill is a long-time broadcast professional and consulting engineer. He may be reached at (insert @ in place[NO-SPAM]) ibcengineering[NOSPAM]juno.com January 25 2001 I found an August 2000 e-mail from you in my Cumbre notes about Ecos del Torbes and have enjoyed finally seeing photos of the station. Many, many thanks for documenting such a fine station. We listen to it regularly and prefer it to our understaffed satellite-glut local stations. Except for the 9640 one-kilowatt unit, the Ecos del Torbes 780 kHz 50 kW transmitter was instantly recognised as a Harris MW-50A, which is a pulse to amplitude design run by many of the US clear channel stations. The 4980 kHz 10 kW transmitter is a Harris BC-10H broadcast transmitter, which uses solid state low power stages and 3X2500 tubes in the modulator and final stage. The BC-10H also has resonators and traps at the third harmonic to square up the final stage plate current and this raises efficiency to about 87%! Ivan Escobar is an engineer after my own heart, as I also ran a Harris AM transmitter when I was a station owner. If you ever confer again with Senor Escobar, tell him his transmitter building interior is cleaner than many US stations and I am very pleased with the excellent fidelity of YVOC! It sounds great on our Watkins-Johnson precision HF receiver in our office, which has a bandpass of better than 8 kHz within 1 dB. You can also tell him by now I have been a listener to Lo Ques de Noche Recuerda for 31 years. Thanks again, Don, for your fine reporting in Latin America and especially for such informative photos. January 26 2001 Harris moved on from the BC-10H and MW-50A to the DX -10 and DX-50 digitally synthesized AM (and shortwave) transmitters, but still include the SX-1 through SX-5 and Gates One through Gates Five solid state 1 kW through 5 kW transmitters. These solid state transmitters have final stage efficiency in excess of 90% and sound as clean as FM. Nonetheless, there are still many superb sounding MW-50A's and BC-10H's still in service and hence Ecos del Torbes is among excellent company. Regarding Ecos del Torbes, our database lists YVSC (9640) as authorised for 10 kW. Does Ivan Escobar have any plans to increase its power from 1 kW? Also, the photo showing the multi-element shortwave antenna, presumably for YVOC based on my received signal strength, suggests it has a reflector behind it and a shorter director element in front. That should give about 3 to 5 dB gain. The effective power in our direction from YVOC may be close to 30 kW. Again, just a conjecture from the photo. Best regards, Bill Sitzman Consulting Engineer This website is maintained by Don Moore, Association of North American Radio Clubs DXer of the Year for 1995.