The alignment in question if for the 50kHz IF of the Drake Rx.
Unfortunately the manual does not give an i/p level for this step, just set it such that there is a slight deflection in the agc voltage.
It could be that both generators have too high an o/p level, but that does not tie in with the OP's statement that the agc voltage does not change, unless I have misunderstood what he is saying and the agc changes when the generators are turned on, but not when cores are adjusted.
73
Jeff G8HUL
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Sent: Saturday, May 24, 2025 08:53
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Subject: Re: [tinysa] TinySA Ultra 50 Khz as a signal generator
The HP209A is used in applications likely wanting -20 dBm to +10dBm.The RF input of a communications receiver might be -110dBm (AGC at max gain, signal just above noise) and about -80dBm to -70dBm for S9 on a signal meter.Wikipedia:"S9 for the HF bands to be a receiver input power of -73 dBm. This is a level of 50 microvolts at the receiver's antenna input assuming the input impedance of the receiver is 50 ohms "Also -73dBm is 30dBuV on 50 Ohms. Often receiver sensitivity is in microvolts at 10dB S/N, though in dBuV in the service/alignment manual. Typical uV (not dBm or dBuV) is over 30 at 100 kHz AM, 3 for SSB and as low as 0.1 UHF SSB. FM is usually more sensitive than AM for 10 db S/N and SSB maybe 30x to 50x more sensitive than AM.I use a 30dB attenuator on the TinySA basic and up to 100 dB on my Rigol tracking generator (fixed 30 dB and a 0 to 70dB that has 10dB steps).Has your Drake 50 kHz rather than 100 kHZ minimum RF in, or is 50 kHz the IF? Note the aerial connection is 50 Ohms, but connections to the IF should be high impedance or you detune it. Plenty of Drake receivers do have a 50 kHz IF.
