Quote:It’s strange that the frequency your counter is registering changes with the setting of the RF output level control. If your generator was converted the way we discussed, the output level should have no effect on what the counter sees, hmmm! I know my setup stays the same regardless. If you plan on using it to work on any ‘hot chassis’ set, be sure the set only is plugged into an isolation transformer before connecting any test equipment. If I understand correctly, you aren’t sure if your generator is working in the broadcast band. It should show up on your counter. Or if you have a known working radio, you can put your output lead from the generator near the radio without even connecting to it and you should be able to pick up and tune in the the signal!
Ron
Hi Ron,
Yes, I find that rather strange as well.
But anyways, as for the Broadcast Band (Band B) on my Signal Generator not working right, its working, but its not working, (either that or its my Philco Radio) because it does show up on my Frequency Counter but its way off from where it should be, 1500 kHz shows up as being around where 1450 should be on the signal Generator's Dial, its the same with Band A, 460 kHz shows up as being 1 line before 450 kHz, but the rest of the signal generator (Band C-E) is spot on where its supposed to be.
Any ideas as to what that's all about?
That's the part where its "working" the part where its not working is where its not producing any test tone.
I checked my signal generator with a known good working solid state clock radio that has a transformer in it (its not a hot chassis unit), and Bands A and B are working as they should (but not very loudly, although I wasn't sure where the AM Antenna was located inside the unit as I was trying to dangle the leads outside of the cabinet to get the signal into the radio), and it was producing a 400 Hz tone, Band C-E though were not working as they should, they were producing a Radio signal as they were cutting out the radio's reception and inserting its own signal at the appropriate spots on the FM Dial (the 10.7 IF Frequency at the lower end of the FM Dial was coming in as it should) and all of the standard FM Alignment Signals were coming in strong with the signal generator on the FM Dial as they should, but the only problem was that there was no 400 Hz test signal (no modulation) on those bands just a loud humming noise that was affected by the RF output knob.
So in a way it is the Signal Generator that's messed up, and in a way it was my Philco radio that was messed up, so its 50/50 here as to what the issue is.
I just ordered some parts for my Radio City Products Signal Generator to see if I can try that out and see if that does any better.
In looking at the schematic for the sg-8, I don’t see any way to adjust each band so the frequency aligns with the dial setting. I’ve never had that problem with my generator. Some bands are off slightly so I just adjust the dial for the frequency I want by watching the counter. Maybe try a new 12AU7! I’ve never used my generator to align an FM radio yet. I am only guessing here but I’m thinking you might not hear the 400Hz modulation on FM. Because the generator puts out amplitude modulation that a frequency modulation set won’t respond to. Anyway, I found the whole assembly manual for your generator here...http://tubularelectronics.com/Heath_Manual_Collection/Heath_Manuals_S/SG-8/SG-8.pdf. Might have some useful info in it for adjusting your generator!
Quote:In looking at the schematic for the sg-8, I don’t see any way to adjust each band so the frequency aligns with the dial setting. I’ve never had that problem with my generator. Some bands are off slightly so I just adjust the dial for the frequency I want by watching the counter. Maybe try a new 12AU7! I’ve never used my generator to align an FM radio yet. I am only guessing here but I’m thinking you might not hear the 400Hz modulation on FM. Because the generator puts out amplitude modulation that a frequency modulation set won’t respond to. Anyway, I found the whole assembly manual for your generator here...http://tubularelectronics.com/Heath_Manual_Collection/Heath_Manuals_S/SG-8/SG-8.pdf. Might have some useful info in it for adjusting your generator!
Ron
OK, well if that's the case then I guess that might explain why I'm not hearing a test tone, although on my Philco even on LW Band I wasn't able to hear anything and it used band 1 in the alignment process.
What I'm thinking is that perhaps I may have to just give up on my SG-8 and just try my luck with the Radio City Products unit, as that one I think will be a better quality unit.
I'll just have to figure out a way to get a BNC Cable to reduce down to Banana Plugs so I can use the RF Hi Output on my Radio City Products Signal Generator for the frequency counter monitoring.
Easy to find doing a search I’ve attached what I think you are looking for! Also, Digikey.com has a selection of various adapters. Amazon also. Happy hunting!
Quote:Easy to find doing a search I’ve attached what I think you are looking for! Also, Digikey.com has a selection of various adapters. Amazon also. Happy hunting!
Yes, something like that, although when I tried to search for something like that at mouser or digikey I came up empty handed, the search results came back saying "no search results came back matching your search criteria" or something like that, and the search terms I used was "Banana Plug to BNC adaptor" (minus the quotes).
Although in my case I'll need longer leads than that because my ground connection is all the way on the lower left hand side of the cabinet (next to the AF In/Out hookup) and the RF Hi Output Banana plug is right next to the RF Lo Output Jack which is on the middle right hand side of the cabinet.
Yes, that worked better, and I did find a cable that had banana plugs on one end and a Male BNC Plug on the other end over at Digikey, I figure that might work better, as it would give me more wire lead to work with, but its $27 for a 3' length of it.
Thanks, but I think I've confirmed using a drill bit that my banana plug jacks are of the 2mm variety so I will need some with 2mm banana plugs on the end unless 4mm banana plugs can be made to fit into a 2mm banana plug jack.
I guess you have a couple of options. The first is to order the cable and a couple of 2mm banana plugs and swap them out.
The second is to order a couple of adapters. I did a search on "4mm to 2mm banana plug adapter" and got some hits... eBay probably has a ton but because of possible shipping delays I'd stay away from Chinese vendors.
I guess a third option is to search for "BNC to 2MM banana plug.".
I just thought of a 4th option. Change the 2mm banana female connector to the more common 4mm female connector.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
(This post was last modified: 05-12-2020, 08:44 AM by Eliot Ness.
Edit Reason: Added option...
)
Quote:I guess you have a couple of options. The first is to order the cable and a couple of 2mm banana plugs and swap them out.
The second is to order a couple of adapters. I did a search on "4mm to 2mm banana plug adapter" and got some hits... eBay probably has a ton but because of possible shipping delays I'd stay away from Chinese vendors.
I guess a third option is to search for "BNC to 2MM banana plug.".
I just thought of a 4th option. Change the 2mm banana female connector to the more common 4mm female connector.
Yes, I was thinking of doing that, because I noticed that on these cables the banana plugs on them are just fastened onto the wire with a setscrew.
EDIT: I just got some parts in for making my Radio City Products signal Generator Work with my BNC Test Cables and I plugded in my Signal Generator, tested it out on a known working solid state GE clock radio from the late 1970s and sure enough it works! It works flawlessly, it puts out a nice clean sounding 400 Hz test tone on all 6 bands of the signal generator (unlike my Heatkit unit).
(This post was last modified: 05-12-2020, 02:52 PM by captainclock1988.)
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