Phonoland

Hi,new to this forum can anyone give me some advise. I purchase my continental,some 20 years ago and have had very little trouble with,it is coupled up with a WQ200 wall box. My problem is that the amp is from a model L main amp number R2620C the per amp is the original R2020A.
Ever since I had purchased the box I note that only one channel works from the per amp and that the main speaker (offer) and tweeter do not work. Am I correct in assuming that the main amp fitted R2620C is the same spec,s as the two amps that were the originally fitted ie L2728 add on power amp and r2777 basic amp. Any info would be greatly appreciated.
John

John, the amps are not the same, at least in the power section. Both continentals had 6973s as final and the L-up had 7868s. In common they both used the center speakers (front woofer and tweeter) wired across both channels for mono output.

--This requires that the phono cart be wired out of phase--

With a record playing remove one of the RCA plugs coming from the tonearm. If phase cancellation is occurring from a normally wired cart some sound will appear in the center speakers. The cure here is to reverse the leads on one channel at the cart. While you are at it, try just one cart plug in each of the input jacks to make sure that both channels are at least producing sound

I've owned Continentals 1&2 along with an "L". Electronically it is certainly possible to modify a later amp to fit a Continental, the mods involved are no big deal. However, if using a preamp from one model with the power amp of another some changes to the interconnect between the two -may- be necessary.

If the above test does not reveal an incorrectly wired cart, you will have to dig into the amp and pre.

If you don't have a schematic, go here: http://www.verntisdale.com/AMIschem.htm to D/L one.

Start with tracing the center speaker wiring back into the amp and to the output transformers.

There are also RCA jacks on the main power amp. These are directly coupled to the output from the preamp and can be used for testing whether there is audio from the preamp.

Another area to check is the volume control. It must be dual section. The original continental used 5k-ohm pots and IIRC, beginning with the "L" 10k-ohm pots were used.

What tools do you have? A decent multimeter is essential here.

There are other points to get into, but try these basic steps first.

Rob/NYC

Hi Rob thanks so much for the very detailed info, I will try what you have listed tomorrow,yes I have a good multi tester.. I must say my continental works Ok so I guess the guy that restored it and sold to me must have done some alterations to the amp. Although the side speakers work ok I would like the front ones to also work. I have noticed that when I connect up two external speakers for the wall box,the two side speakers have equal volume ( on the jukebox ). If I disconnect them the left speaker has a much lower volume.
Once again thanks will let you know how I get on
Take Care John in Spain.

PS Rob,forgot to ask,can I connect left and right terminal strips on the r2620 amp as per the L2728 power amp and R2777 basic amp Hope understand what I mean.
John Spain,

Hi I have sorted out center speakers by connecting left and right speaker wires as per the r2620 not the r2777 as was connected. Now very pleased with the all round sound. On the pre amp r2020. The left channel produces no sound, so I guess the pre amp needs looking at. Not sure if I should worry as sound is great as it is. Would I be correct in saying if both channels were working I would hear little difference as most of records I use are not stereo.
Like your thoughts
John in Spain

John, when you say that the preamp produces no sound, have you tried the following:

-Swap tubes between channels.

-Look for the presence of audio at the volume control. Be sure it is a stereo (dual pot) unit.

-Use an AC meter to check for audio at the RCA jacks on the power amp section (you may have already done this).

The link plug between pre and power amp is a known source of erratic connection on all electronics of this era.

Given it's age its really questionable whether it is advisable to use the amp if it has not been -properly- rebuilt.

I suggest opening both amp chassis and see if the at least the capacitors have been replaced.

Rob

Hi can any one help me I have a ami conti 2 I need to fit a new cartridge to the tone arm,I note that the arm has 2 sets of wires to the cartridge each has one red and one black. The replacement cartridge has four pins coloured coded,how do I connect the red/black wires to the four pins,do they need to be phased.
Thanks
John

Hi John,
I don't know what the new cart has--but the two red wires are the "hots", and the two blacks are grounds, on the old one. Wire your new one (hopefully the same type !), the same as the old one--- Ron Rich

Hi Ron thanks for your reply,yes the replacement cart is the same as the old one.
I will wire the same as old one,I might try to wire the other way round on one channel to see if it makes any difference.
Again thanks for reply.
Take care John

Hi John,
Wire it whichever way it has the most bass response.
Ron Rich