This concerns the EMUD 196 referenced in a previous post below. Edd was helping me out but seems to have lost interest. The AM band works well. On FM, stations progress in correct sequence up to 97.9 - then the next station I receive is 92.3 at 99 on the dial and the sequence begins again, topping out at station 100.8 at about 108 on the dial. The replicated stations sound about equivalent to their "lower scale" counterparts but seem to be about 7Mhz off. I inspected the IF cans - they are packed with dust and a white sealer - no signs of tampering - in fact, other than a prior tube change, the chassis looks virgin.

I tried an external ant to improve the AM reception and then tried disconnecting the internal FM dipole and hooking up to an ext long wire dipole. The lower end gets some overlap of strong stations but the upper end now gets stations above 97.9 where they should be. The int dipole is folded within the cabinet and looks intact. A link to the schematic is available in the prior post. So there you have it... I look forward to your thoughts..

Au contriere...Messr Bill

No loss of interest.......what-so-ever. I just need to go to the off...and thats HEAVY on the waaaayy OFF site .... storage area of the manual as I only got the schema initially for you. With this new problem on hand I now need to inspect the physical aspects of the units on board- dedicated FM tumer, as it is not built in a spread out, on the chassis type of construction, as is commonly done.

I initially was considering an image type of situation, ( but your indication of the pristine condition of their seals, sort of indicates otherwise) or else the massive shifting of the freq of the local osc was such that the unit was double dipping the whole FM band. ( Do you have a scanner type of receiver that will cover 100-125 Mhz ? )

Initially...until I hopefully get the other data on the unit over the weekend.... check the pressure grounding action of the rotor portion of the FM tuning condensers for making low resistance contact action, or that no white / black oxide powder has built up on it.

Also the schematic shows no special traps or out of the normal circuitry in the problematic FM section, but it almost sounds as if the inductive tuning component(s) of the RF stage might not be connected in good by their switching medium....the pushbutton switch contacts..... Therefore, do a good ohmic check of that RF coil and any contacts associated with it in being switched into circuit while the pushbuttons are engaged into, while in the FM mode.

I'm particularly thinking of the M3 contacts up at the secondary coil of the 1st FM IF at the plate circuitry of the FM mixer. Also look down at the switch portion just down from V3 2nd IF and its grid circuitry.


Aside.....did the 4 ufd cap off pin 7 ..plate... of the V4 ratio det get changed?


73's de Edd

:This concerns the EMUD 196 referenced in a previous post below. Edd was helping me out but seems to have lost interest. The AM band works well. On FM, stations progress in correct sequence up to 97.9 - then the next station I receive is 92.3 at 99 on the dial and the sequence begins again, topping out at station 100.8 at about 108 on the dial. The replicated stations sound about equivalent to their "lower scale" counterparts but seem to be about 7Mhz off. I inspected the IF cans - they are packed with dust and a white sealer - no signs of tampering - in fact, other than a prior tube change, the chassis looks virgin.
:
:I tried an external ant to improve the AM reception and then tried disconnecting the internal FM dipole and hooking up to an ext long wire dipole. The lower end gets some overlap of strong stations but the upper end now gets stations above 97.9 where they should be. The int dipole is folded within the cabinet and looks intact. A link to the schematic is available in the prior post. So there you have it... I look forward to your thoughts..
:

Qui s'excuse s'accuse...My most sincere apologies Edd - my impatience is showing...perhaps because I'll be on the road most of the next week and have little time to devote to my ray-dieu-oh love affair - or perhaps because the mademoiselle is griping about getting this Teutonic tubed wonder off of her breakfast table ASAP. But I relish the reply... and I do recall a cursory check of C2 - but I will check again. The tuning cap "looks" clean - but I will put a meter to it and the suggested switches on my return. There are a couple of those white 'rubberized' caps - like the shorted one in the output - well beneath the tuning cap that are next to impossible to reach. A lot of stuff is permanently riveted on this EMUD and a bear to get too. It looks as though I'll have to temporarily dislodge the pwr txmr to get to those caps. So - excuse my eager restiveness.. I will be in touch with some observations soon. Thanks... Bill