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

Dynaco, Dynakits, etc.
#9

I have a ST-70, PAS-2, and FM-1 (with multiplexer) that my Dad built in 1961 and '62. I have been through the ST-70 and the preamp and have replaced all of the black tubular caps, the electrolytics, a couple of out of spec micas, and a few resistors> I matched component pairs where noted on the schematic or parts list. I replaced the electrolytics in the tuner, but not the other caps because they are all ceramic.

One of the EL-34s was missing, so I replaced them with a matched quad of Russian Mullards. After a while I replaced the 7199s with 6GHAs with the adapter. The whole system sounds great, given the mediocre quality of my speakers. The sensitivity of the FM is really impressive.

I've had intermittent problems with balance between the two stereo channels. Replacing the 12AX7s in the PAS-2 preamp with a matched quad seemed to work, but now, only a few days later, the ST-70 developed a balance problem! It's giving me fits. I'll probably start a thread on it once I've had a chance to dig into it and check a few obvious things.

And if that weren't enough frustration, the FM-1 suddenly developed a loud hum that is independent of the volume control. If I turn the tuner volume all the way up and the preamp volume way down, the hum is gone, but it is quite horrible with the volume controls set any other way. Another thread to be started later, I suppose.

John Honeycutt


Messages In This Thread
Dynaco, Dynakits, etc. - by Phlogiston - 04-01-2014, 06:10 PM
RE: Dynaco, Dynakits, etc. - by Ron Ramirez - 04-04-2014, 09:50 PM
RE: Dynaco, Dynakits, etc. - by TV MAN - 04-05-2014, 10:55 AM
RE: Dynaco, Dynakits, etc. - by codefox1 - 04-05-2014, 12:48 PM
RE: Dynaco, Dynakits, etc. - by Phlogiston - 04-05-2014, 05:23 PM
RE: Dynaco, Dynakits, etc. - by Raleigh - 04-11-2014, 10:22 AM
RE: Dynaco, Dynakits, etc. - by Phlogiston - 04-11-2014, 11:35 AM
RE: Dynaco, Dynakits, etc. - by Raleigh - 04-11-2014, 02:39 PM
RE: Dynaco, Dynakits, etc. - by Phlogiston - 04-11-2014, 05:57 PM
RE: Dynaco, Dynakits, etc. - by wireless - 04-23-2014, 07:34 PM
RE: Dynaco, Dynakits, etc. - by radiohenry - 04-27-2014, 08:11 AM
RE: Dynaco, Dynakits, etc. - by Joeztech - 06-05-2014, 07:40 PM
RE: Dynaco, Dynakits, etc. - by Arran - 06-05-2014, 11:09 PM
RE: Dynaco, Dynakits, etc. - by exray - 06-12-2014, 05:26 PM
RE: Dynaco, Dynakits, etc. - by Phlogiston - 06-12-2014, 06:21 PM
RE: Dynaco, Dynakits, etc. - by bfrohwein - 06-12-2014, 08:43 PM
RE: Dynaco, Dynakits, etc. - by gregb - 06-12-2014, 08:50 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Heathkit Sweep Generator TS-4
Ron Instead of Quick reply, go to New Reply, then go to the title of the very first post, and change the title text the...morzh — 02:00 PM
6TPZ and 5TPO Radio Help
I am not a specialist in car radios. I suspect they might use vibrators to convert 12V to acceptable tube voltages, so ...morzh — 01:58 PM
6TPZ and 5TPO Radio Help
Welcome to the Phorum, R3Sons! I have very limited experience with car radios other than installing custom radios back ...GarySP — 01:08 PM
462ron
OK, I need to rename this thread to say..Eico 368 TV/FM Sweep Generator instead of the current title..Heathkit Sweep Gen...462ron — 12:49 PM
6TPZ and 5TPO Radio Help
Hello, I have a Philco (Ford) 6TPZ and a 5TPO radio.  I replaced the electrolytic capacitors in both.  I have the SAMS m...R3Sons — 12:29 PM
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

[-]
Who's Online
There are currently no members online.

>