Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

AM transmitter issues
#3

+1 on what Vinzer said. However, check the carrtridge. Most "phono" preamps, especially those little boxes with no controls) are for magnetic cartridges. If the RC/88 has a crystal or ceramic cartridge in it, it will overdrive a magnetic preamp. Plug the preamp that the RC88 is feeding into the "line level" input of an amp, to confirm that it works. If the Spitfire has a "line level" input and the phono and preamp are functional, distortion should not be an issue. Otherwise, get a 100K audio taper pot, connect the output of the preamp between the 2 outer legs (ensure the leg closest to minimum is the common), and the transmitter between the center (wiper) contact and the common leg.

Hopefully this works.

Re the SSTRAN, I understand that they stopped making them but still support them. If possible, tune the SSTRAN to an OCCUPIED channel, turn it off and tune that channel on the radio. Power up the SSTRAN. If no difference is heard, the transmitter is dead. I don't know how many stages that there are to the transmitter, but either the oscillator, RF amp or power is the issue. If the unit was run without an antenna or a poorly matched antenna, the output transistor may have blown (although these are only 100mW units and I hope that the output transistor was a little heftier than that). Do you have a schematic? Post it, and we all will see if we can help. I don't have the SSTRAN (I have a Vector kit and a Talking House) but several other Phriends on the Phorum do have them.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


Messages In This Thread
AM transmitter issues - by oldschoolphotoguy - 04-15-2023, 06:39 PM
RE: AM transmitter issues - by vinzer - 04-15-2023, 08:03 PM
RE: AM transmitter issues - by MrFixr55 - 04-16-2023, 10:37 AM
RE: AM transmitter issues - by Radioroslyn - 04-16-2023, 12:02 PM
RE: AM transmitter issues - by radiorich - 04-16-2023, 02:33 PM
RE: AM transmitter issues - by oldschoolphotoguy - 04-21-2023, 05:51 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
The list of my radio & TV collection!
Hello Peter, Thank you for posting that !! Sincerely Richardradiorich — 09:40 AM
Eico 232 VTVM Schematic
It's a microwave antenna. ?;-p?. I substituted 1N4002s off the 6.3 vac winding for the 1.5 volt battery. Uniprobe is the...RodB — 05:50 PM
Eico 232 VTVM Schematic
Try BAMA for a schematic. Looks like a replacement power source for the D battery has been installed. The tube may be...Chas — 04:51 PM
Eico 232 VTVM Schematic
Is that a battery holder?morzh — 04:43 PM
Eico 232 VTVM Schematic
A friend gave me this Eico 232 VTVM and I'm having trouble locating the schematic for it. This one seems to be a later v...RodB — 04:17 PM
Var resistor id
Considering what it is in series with, I doubt there should be any power requirements. Of course, we should know wher...morzh — 03:23 PM
Var resistor id
Trim pot, about 1/2 watt part of focus divider. As stated 2k ohms. This appears to be a rusty chassis, resolder all ...Chas — 03:19 PM
Var resistor id
Its a Sylvania 400 oscilloscope. here is a clip of r-100. Would be nice to know the current required. Not listed in part...Martinj — 02:10 PM
The list of my radio & TV collection!
Thanks Richard. I hope you enjoy it. Here I have created an English section on the history of radio with videos in Engl...RadioSvit — 10:23 AM
The list of my radio & TV collection!
Hello RadioSvit, first all happy new year ! I will watch your new videos this week. Sincerely Richardradiorich — 09:19 AM

[-]
Who's Online
There are currently 8113 online users. [Complete List]
» 2 Member(s) | 8111 Guest(s)
AvatarAvatar

>