lowband Syntor-x extender working?

[n3chu]

Hi all.I have a Syntor-x lowband that I put on 10 and 6M about 15 years ago and it has worked well except altenater whine that I fixed and still have auxillery AC fan noise. I remember setting up the extender for the 6M band as it wouldnt cover both bands effectivly. my question is is there a simple way to tell if the extender is working or not?. like a voltage at a test point? The fan noise has got me stumped and I put a new fan in and shielded the power cord from the fan controller to the fan and it didnt help the noise, I had put several caps acrossed the old fan as close to it as I could but no help so that made me think maybe the extender might not be turned on. any help appreciated. been listening to this fan for 6 years. thank you very much. Davie n-3-c-h-u-at atlanticbb dot net

[WB6NVH]

The extender is optimized for pulse type ignition noise and does not work very well (if at all) on certain other types of noise, such as, for example, noise from high tension lines (or maybe fans.)

I have had better luck using ferrite chokes in series with fan wires as opposed to bypass capacitors to ground, but each situation seems different.

Once upon a time in the 1960's the extender in a Motran could be turned off with a switch on the control head and measured at Meter position # 3 on the test set. Then the Micor came along and put the extender switch spring-loaded normally on, on the rear of the clamshell head, and deleted the switch altogether on the Systems 90 version heads. Then the Syntor X, with no on-off switch. For us, it's certainly useful to have an on-off switch for the extender. Apparently for everyone else, such as the original user, it was just confusing.

50 MHz is approximately in the center of the noise intensity spectrum so the noise blankers are generally set to sample at that end of the tuning where possible.

I am not near my manual but as I recall there's a test point to use when aligning the Syntor X extender. If that reads normally when you align the extender, I would feel safe presuming that the extender is working. If I recall, there are also a couple of ways to disable the extender, as a test, it's just not convenient. I haven't programmed one in a few years, but wasn't there a setting in software to shut it off?

The extender was normally tested using the extender test set, basically a variable pulse generator, back in the Micor era. I see they discontinued that test set by the Syntor X era. I wonder why.

A pulse generator works just as well, but not everyone has one of those either. I have the typical pulse rate settings for extender testing written down somewhere if anyone is interested.

[n3chu]

Thanks for your reply, I found my manual and the extender is for pulse and DC motors.the fan isnt a constant whine (goes from a low whine up to a high whine)untill it reaches max speed. I found the test point and the voltage is about 2.1 volts and the manual said to tune the extender 3 mhz from the operating freq so think I tuned it to 49.525, I dont seem to get pulse noise. put the new fan with shielding on today but the fan isnt balanced so feel a viberation when its on so may have to put the old one back on. the old fan had little balancing clips on some of the blades. I tried the mix 31 snap ons also .1 and .01 caps in parallel acrosed the power cable with no results. I havent givin up yet but am running out of ideas. Davie